gpcontrib/pg_hint_plan/pg_hint_plan.c (3,664 lines of code) (raw):
/*-------------------------------------------------------------------------
*
* pg_hint_plan.c
* hinting on how to execute a query for PostgreSQL
*
* Copyright (c) 2012-2020, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
*
*-------------------------------------------------------------------------
*/
#include <string.h>
#include "postgres.h"
#include "access/genam.h"
#include "access/hash.h"
#include "access/heapam.h"
#include "access/relation.h"
#include "catalog/pg_collation.h"
#include "catalog/pg_index.h"
#include "commands/prepare.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
#include "nodes/params.h"
#include "optimizer/appendinfo.h"
#include "optimizer/clauses.h"
#include "optimizer/cost.h"
/*
* GPDB does not support geqo planner
*/
#if 0
#include "optimizer/geqo.h"
#endif
#include "optimizer/joininfo.h"
#include "optimizer/orca.h"
#include "optimizer/optimizer.h"
#include "optimizer/pathnode.h"
#include "optimizer/paths.h"
#include "optimizer/plancat.h"
#include "optimizer/planner.h"
#include "optimizer/prep.h"
#include "optimizer/restrictinfo.h"
#include "parser/analyze.h"
#include "parser/parsetree.h"
#include "parser/scansup.h"
#include "parser/scanner.h"
#include "partitioning/partbounds.h"
#include "tcop/utility.h"
#include "utils/builtins.h"
#include "utils/float.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/rel.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "utils/resowner.h"
#include "utils/queryjumble.h"
#include "catalog/pg_class.h"
#include "executor/spi.h"
#include "catalog/pg_type.h"
#include "plpgsql.h"
/* PostgreSQL */
#include "access/htup_details.h"
#ifdef PG_MODULE_MAGIC
PG_MODULE_MAGIC;
#endif
#define BLOCK_COMMENT_START "/*"
#define BLOCK_COMMENT_END "*/"
#define HINT_COMMENT_KEYWORD "+"
#define HINT_START BLOCK_COMMENT_START HINT_COMMENT_KEYWORD
#define HINT_END BLOCK_COMMENT_END
/* hint keywords */
#define HINT_SEQSCAN "SeqScan"
#define HINT_INDEXSCAN "IndexScan"
#define HINT_INDEXSCANREGEXP "IndexScanRegexp"
#define HINT_BITMAPSCAN "BitmapScan"
#define HINT_BITMAPSCANREGEXP "BitmapScanRegexp"
#define HINT_TIDSCAN "TidScan"
#define HINT_NOSEQSCAN "NoSeqScan"
#define HINT_NOINDEXSCAN "NoIndexScan"
#define HINT_NOBITMAPSCAN "NoBitmapScan"
#define HINT_NOTIDSCAN "NoTidScan"
#define HINT_INDEXONLYSCAN "IndexOnlyScan"
#define HINT_INDEXONLYSCANREGEXP "IndexOnlyScanRegexp"
#define HINT_NOINDEXONLYSCAN "NoIndexOnlyScan"
#define HINT_PARALLEL "Parallel"
#define HINT_NESTLOOP "NestLoop"
#define HINT_MERGEJOIN "MergeJoin"
#define HINT_HASHJOIN "HashJoin"
#define HINT_NONESTLOOP "NoNestLoop"
#define HINT_NOMERGEJOIN "NoMergeJoin"
#define HINT_NOHASHJOIN "NoHashJoin"
#define HINT_LEADING "Leading"
#define HINT_SET "Set"
#define HINT_ROWS "Rows"
#define HINT_ARRAY_DEFAULT_INITSIZE 8
#define hint_ereport(str, detail) hint_parse_ereport(str, detail)
#define hint_parse_ereport(str, detail) \
do { \
ereport(pg_hint_plan_parse_message_level, \
(errmsg("pg_hint_plan: hint syntax error at or near \"%s\"", (str)), \
errdetail detail)); \
} while(0)
#define skip_space(str) \
while (isspace(*str)) \
str++;
enum
{
ENABLE_SEQSCAN = 0x01,
ENABLE_INDEXSCAN = 0x02,
ENABLE_BITMAPSCAN = 0x04,
ENABLE_TIDSCAN = 0x08,
ENABLE_INDEXONLYSCAN = 0x10
} SCAN_TYPE_BITS;
enum
{
ENABLE_NESTLOOP = 0x01,
ENABLE_MERGEJOIN = 0x02,
ENABLE_HASHJOIN = 0x04
} JOIN_TYPE_BITS;
#define ENABLE_ALL_SCAN (ENABLE_SEQSCAN | ENABLE_INDEXSCAN | \
ENABLE_BITMAPSCAN | ENABLE_TIDSCAN | \
ENABLE_INDEXONLYSCAN)
#define ENABLE_ALL_JOIN (ENABLE_NESTLOOP | ENABLE_MERGEJOIN | ENABLE_HASHJOIN)
#define DISABLE_ALL_SCAN 0
#define DISABLE_ALL_JOIN 0
/* hint keyword of enum type*/
typedef enum HintKeyword
{
HINT_KEYWORD_SEQSCAN,
HINT_KEYWORD_INDEXSCAN,
HINT_KEYWORD_INDEXSCANREGEXP,
HINT_KEYWORD_BITMAPSCAN,
HINT_KEYWORD_BITMAPSCANREGEXP,
HINT_KEYWORD_TIDSCAN,
HINT_KEYWORD_NOSEQSCAN,
HINT_KEYWORD_NOINDEXSCAN,
HINT_KEYWORD_NOBITMAPSCAN,
HINT_KEYWORD_NOTIDSCAN,
HINT_KEYWORD_INDEXONLYSCAN,
HINT_KEYWORD_INDEXONLYSCANREGEXP,
HINT_KEYWORD_NOINDEXONLYSCAN,
HINT_KEYWORD_NESTLOOP,
HINT_KEYWORD_MERGEJOIN,
HINT_KEYWORD_HASHJOIN,
HINT_KEYWORD_NONESTLOOP,
HINT_KEYWORD_NOMERGEJOIN,
HINT_KEYWORD_NOHASHJOIN,
HINT_KEYWORD_LEADING,
HINT_KEYWORD_SET,
HINT_KEYWORD_ROWS,
HINT_KEYWORD_PARALLEL,
HINT_KEYWORD_UNRECOGNIZED
} HintKeyword;
#define SCAN_HINT_ACCEPTS_INDEX_NAMES(kw) \
(kw == HINT_KEYWORD_INDEXSCAN || \
kw == HINT_KEYWORD_INDEXSCANREGEXP || \
kw == HINT_KEYWORD_INDEXONLYSCAN || \
kw == HINT_KEYWORD_INDEXONLYSCANREGEXP || \
kw == HINT_KEYWORD_BITMAPSCAN || \
kw == HINT_KEYWORD_BITMAPSCANREGEXP)
typedef struct Hint Hint;
typedef struct HintState HintState;
typedef Hint *(*HintCreateFunction) (const char *hint_str,
const char *keyword,
HintKeyword hint_keyword);
typedef void (*HintDeleteFunction) (Hint *hint);
typedef void (*HintDescFunction) (Hint *hint, StringInfo buf, bool nolf);
typedef int (*HintCmpFunction) (const Hint *a, const Hint *b);
typedef const char *(*HintParseFunction) (Hint *hint, HintState *hstate,
Query *parse, const char *str);
/* hint types */
#define NUM_HINT_TYPE 6
typedef enum HintType
{
HINT_TYPE_SCAN_METHOD,
HINT_TYPE_JOIN_METHOD,
HINT_TYPE_LEADING,
HINT_TYPE_SET,
HINT_TYPE_ROWS,
HINT_TYPE_PARALLEL
} HintType;
typedef enum HintTypeBitmap
{
HINT_BM_SCAN_METHOD = 1,
HINT_BM_PARALLEL = 2
} HintTypeBitmap;
static const char *HintTypeName[] = {
"scan method",
"join method",
"leading",
"set",
"rows",
"parallel"
};
/* hint status */
typedef enum HintStatus
{
HINT_STATE_NOTUSED = 0, /* specified relation not used in query */
HINT_STATE_USED, /* hint is used */
HINT_STATE_DUPLICATION, /* specified hint duplication */
HINT_STATE_ERROR /* execute error (parse error does not include
* it) */
} HintStatus;
#define hint_state_enabled(hint) ((hint)->base.state == HINT_STATE_NOTUSED || \
(hint)->base.state == HINT_STATE_USED)
static unsigned int qno = 0;
static unsigned int msgqno = 0;
static char qnostr[32];
static const char *current_hint_str = NULL;
static HintState *hstate = NULL;
/*
* However we usually take a hint stirng in post_parse_analyze_hook, we still
* need to do so in planner_hook when client starts query execution from the
* bind message on a prepared query. This variable prevent duplicate and
* sometimes harmful hint string retrieval.
*/
static bool current_hint_retrieved = false;
/* common data for all hints. */
struct Hint
{
const char *hint_str; /* must not do pfree */
const char *keyword; /* must not do pfree */
HintKeyword hint_keyword;
HintType type;
HintStatus state;
HintDeleteFunction delete_func;
HintDescFunction desc_func;
HintCmpFunction cmp_func;
HintParseFunction parse_func;
};
/* scan method hints */
typedef struct ScanMethodHint
{
Hint base;
char *relname;
List *indexnames;
bool regexp;
unsigned char enforce_mask;
} ScanMethodHint;
typedef struct ParentIndexInfo
{
bool indisunique;
Oid method;
List *column_names;
char *expression_str;
Oid *indcollation;
Oid *opclass;
int16 *indoption;
char *indpred_str;
} ParentIndexInfo;
/* join method hints */
typedef struct JoinMethodHint
{
Hint base;
int nrels;
int inner_nrels;
char **relnames;
unsigned char enforce_mask;
Relids joinrelids;
Relids inner_joinrelids;
} JoinMethodHint;
/* join order hints */
typedef struct OuterInnerRels
{
char *relation;
List *outer_inner_pair;
} OuterInnerRels;
typedef struct LeadingHint
{
Hint base;
List *relations; /* relation names specified in Leading hint */
OuterInnerRels *outer_inner;
} LeadingHint;
/* change a run-time parameter hints */
typedef struct SetHint
{
Hint base;
char *name; /* name of variable */
char *value;
List *words;
} SetHint;
/* rows hints */
typedef enum RowsValueType {
RVT_ABSOLUTE, /* Rows(... #1000) */
RVT_ADD, /* Rows(... +1000) */
RVT_SUB, /* Rows(... -1000) */
RVT_MULTI, /* Rows(... *1.2) */
} RowsValueType;
typedef struct RowsHint
{
Hint base;
int nrels;
int inner_nrels;
char **relnames;
Relids joinrelids;
Relids inner_joinrelids;
char *rows_str;
RowsValueType value_type;
double rows;
} RowsHint;
/* parallel hints */
typedef struct ParallelHint
{
Hint base;
char *relname;
char *nworkers_str; /* original string of nworkers */
int nworkers; /* num of workers specified by Worker */
bool force_parallel; /* force parallel scan */
} ParallelHint;
/*
* Describes a context of hint processing.
*/
struct HintState
{
char *hint_str; /* original hint string */
/* all hint */
int nall_hints; /* # of valid all hints */
int max_all_hints; /* # of slots for all hints */
Hint **all_hints; /* parsed all hints */
/* # of each hints */
int num_hints[NUM_HINT_TYPE];
/* for scan method hints */
ScanMethodHint **scan_hints; /* parsed scan hints */
/* Initial values of parameters */
int init_scan_mask; /* enable_* mask */
int init_nworkers; /* max_parallel_workers_per_gather */
/* min_parallel_table_scan_size*/
int init_min_para_tablescan_size;
/* min_parallel_index_scan_size*/
int init_min_para_indexscan_size;
double init_paratup_cost; /* parallel_tuple_cost */
double init_parasetup_cost;/* parallel_setup_cost */
PlannerInfo *current_root; /* PlannerInfo for the followings */
Index parent_relid; /* inherit parent of table relid */
ScanMethodHint *parent_scan_hint; /* scan hint for the parent */
ParallelHint *parent_parallel_hint; /* parallel hint for the parent */
List *parent_index_infos; /* list of parent table's index */
JoinMethodHint **join_hints; /* parsed join hints */
int init_join_mask; /* initial value join parameter */
List **join_hint_level;
LeadingHint **leading_hint; /* parsed Leading hints */
SetHint **set_hints; /* parsed Set hints */
GucContext context; /* which GUC parameters can we set? */
RowsHint **rows_hints; /* parsed Rows hints */
ParallelHint **parallel_hints; /* parsed Parallel hints */
int log_level; /* debug_print log level */
};
/*
* Describes a hint parser module which is bound with particular hint keyword.
*/
typedef struct HintParser
{
char *keyword;
HintCreateFunction create_func;
HintKeyword hint_keyword;
} HintParser;
/* Module callbacks */
void _PG_init(void);
void _PG_fini(void);
static void push_hint(HintState *hstate);
static void pop_hint(void);
static void pg_hint_plan_post_parse_analyze(ParseState *pstate, Query *query, JumbleState *jstate);
static void pg_hint_plan_ProcessUtility(PlannedStmt *pstmt,
const char *queryString,
bool readOnlyTree,
ProcessUtilityContext context,
ParamListInfo params, QueryEnvironment *queryEnv,
DestReceiver *dest, QueryCompletion *qc);
static RelOptInfo *
pg_hint_plan_make_join_rel(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2);
static void
pg_hint_plan_add_paths_to_joinrel(PlannerInfo *root,
RelOptInfo *joinrel,
RelOptInfo *outerrel,
RelOptInfo *innerrel,
JoinType jointype,
SpecialJoinInfo *sjinfo,
List *restrictlist);
#ifdef USE_ORCA
static void *external_plan_hint_hook(Query *parse);
#endif
static PlannedStmt *pg_hint_plan_planner(Query *parse, const char *query_string, int cursorOptions,
ParamListInfo boundParams);
static RelOptInfo *pg_hint_plan_join_search(PlannerInfo *root,
int levels_needed,
List *initial_rels);
/* Scan method hint callbacks */
static Hint *ScanMethodHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword);
static void ScanMethodHintDelete(ScanMethodHint *hint);
static void ScanMethodHintDesc(ScanMethodHint *hint, StringInfo buf, bool nolf);
static int ScanMethodHintCmp(const ScanMethodHint *a, const ScanMethodHint *b);
static const char *ScanMethodHintParse(ScanMethodHint *hint, HintState *hstate,
Query *parse, const char *str);
/* Join method hint callbacks */
static Hint *JoinMethodHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword);
static void JoinMethodHintDelete(JoinMethodHint *hint);
static void JoinMethodHintDesc(JoinMethodHint *hint, StringInfo buf, bool nolf);
static int JoinMethodHintCmp(const JoinMethodHint *a, const JoinMethodHint *b);
static const char *JoinMethodHintParse(JoinMethodHint *hint, HintState *hstate,
Query *parse, const char *str);
/* Leading hint callbacks */
static Hint *LeadingHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword);
static void LeadingHintDelete(LeadingHint *hint);
static void LeadingHintDesc(LeadingHint *hint, StringInfo buf, bool nolf);
static int LeadingHintCmp(const LeadingHint *a, const LeadingHint *b);
static const char *LeadingHintParse(LeadingHint *hint, HintState *hstate,
Query *parse, const char *str);
/* Set hint callbacks */
static Hint *SetHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword);
static void SetHintDelete(SetHint *hint);
static void SetHintDesc(SetHint *hint, StringInfo buf, bool nolf);
static int SetHintCmp(const SetHint *a, const SetHint *b);
static const char *SetHintParse(SetHint *hint, HintState *hstate, Query *parse,
const char *str);
/* Rows hint callbacks */
static Hint *RowsHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword);
static void RowsHintDelete(RowsHint *hint);
static void RowsHintDesc(RowsHint *hint, StringInfo buf, bool nolf);
static int RowsHintCmp(const RowsHint *a, const RowsHint *b);
static const char *RowsHintParse(RowsHint *hint, HintState *hstate,
Query *parse, const char *str);
/* Parallel hint callbacks */
static Hint *ParallelHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword);
static void ParallelHintDelete(ParallelHint *hint);
static void ParallelHintDesc(ParallelHint *hint, StringInfo buf, bool nolf);
static int ParallelHintCmp(const ParallelHint *a, const ParallelHint *b);
static const char *ParallelHintParse(ParallelHint *hint, HintState *hstate,
Query *parse, const char *str);
static void quote_value(StringInfo buf, const char *value);
static const char *parse_quoted_value(const char *str, char **word,
bool truncate);
static void
set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte);
void pg_hint_plan_join_search_one_level(PlannerInfo *root, int level);
void pg_hint_plan_set_rel_pathlist(PlannerInfo * root, RelOptInfo *rel,
Index rti, RangeTblEntry *rte);
RelOptInfo *pg_hint_plan_make_join_rel(PlannerInfo *root, RelOptInfo *rel1,
RelOptInfo *rel2);
static void pg_hint_plan_plpgsql_stmt_beg(PLpgSQL_execstate *estate,
PLpgSQL_stmt *stmt);
static void pg_hint_plan_plpgsql_stmt_end(PLpgSQL_execstate *estate,
PLpgSQL_stmt *stmt);
static void plpgsql_query_erase_callback(ResourceReleasePhase phase,
bool isCommit,
bool isTopLevel,
void *arg);
static int set_config_option_noerror(const char *name, const char *value,
GucContext context, GucSource source,
GucAction action, bool changeVal, int elevel);
static void setup_scan_method_enforcement(ScanMethodHint *scanhint,
HintState *state);
static int set_config_int32_option(const char *name, int32 value,
GucContext context);
static int set_config_double_option(const char *name, double value,
GucContext context);
static char *generate_normalized_query(JumbleState *jstate, const char *query,
int query_loc, int *query_len_p, int encoding);
static void fill_in_constant_lengths(JumbleState *jstate, const char *query,
int query_loc);
static int comp_location(const void *a, const void *b);
/* GUC variables */
static bool pg_hint_plan_enable_hint = true;
static int debug_level = 0;
static int pg_hint_plan_parse_message_level = INFO;
static int pg_hint_plan_debug_message_level = LOG;
/* Default is off, to keep backward compatibility. */
static bool pg_hint_plan_enable_hint_table = false;
static int plpgsql_recurse_level = 0; /* PLpgSQL recursion level */
static int recurse_level = 0; /* recursion level incl. direct SPI calls */
static int hint_inhibit_level = 0; /* Inhibit hinting if this is above 0 */
/* (This could not be above 1) */
static int max_hint_nworkers = -1; /* Maximum nworkers of Workers hints */
static const struct config_enum_entry parse_messages_level_options[] = {
{"debug", DEBUG2, true},
{"debug5", DEBUG5, false},
{"debug4", DEBUG4, false},
{"debug3", DEBUG3, false},
{"debug2", DEBUG2, false},
{"debug1", DEBUG1, false},
{"log", LOG, false},
{"info", INFO, false},
{"notice", NOTICE, false},
{"warning", WARNING, false},
{"error", ERROR, false},
/*
* {"fatal", FATAL, true},
* {"panic", PANIC, true},
*/
{NULL, 0, false}
};
static const struct config_enum_entry parse_debug_level_options[] = {
{"off", 0, false},
{"on", 1, false},
{"detailed", 2, false},
{"verbose", 3, false},
{"0", 0, true},
{"1", 1, true},
{"2", 2, true},
{"3", 3, true},
{"no", 0, true},
{"yes", 1, true},
{"false", 0, true},
{"true", 1, true},
{NULL, 0, false}
};
/* Saved hook values in case of unload */
static post_parse_analyze_hook_type prev_post_parse_analyze_hook = NULL;
static planner_hook_type prev_planner = NULL;
static join_search_hook_type prev_join_search = NULL;
static set_rel_pathlist_hook_type prev_set_rel_pathlist = NULL;
static ProcessUtility_hook_type prev_ProcessUtility_hook = NULL;
static ExecutorEnd_hook_type prev_ExecutorEnd = NULL;
static make_join_rel_hook_type prev_make_join_rel_hook = NULL;
static add_paths_to_joinrel_hook_type prev_add_paths_to_joinrel_hook = NULL;
#ifdef USE_ORCA
static plan_hint_hook_type prev_plan_hint_hook = NULL;
#endif
/* Hold reference to currently active hint */
static HintState *current_hint_state = NULL;
/*
* List of hint contexts. We treat the head of the list as the Top of the
* context stack, so current_hint_state always points the first element of this
* list.
*/
static List *HintStateStack = NIL;
static const HintParser parsers[] = {
{HINT_SEQSCAN, ScanMethodHintCreate, HINT_KEYWORD_SEQSCAN},
{HINT_INDEXSCAN, ScanMethodHintCreate, HINT_KEYWORD_INDEXSCAN},
{HINT_INDEXSCANREGEXP, ScanMethodHintCreate, HINT_KEYWORD_INDEXSCANREGEXP},
{HINT_BITMAPSCAN, ScanMethodHintCreate, HINT_KEYWORD_BITMAPSCAN},
{HINT_BITMAPSCANREGEXP, ScanMethodHintCreate,
HINT_KEYWORD_BITMAPSCANREGEXP},
{HINT_TIDSCAN, ScanMethodHintCreate, HINT_KEYWORD_TIDSCAN},
{HINT_NOSEQSCAN, ScanMethodHintCreate, HINT_KEYWORD_NOSEQSCAN},
{HINT_NOINDEXSCAN, ScanMethodHintCreate, HINT_KEYWORD_NOINDEXSCAN},
{HINT_NOBITMAPSCAN, ScanMethodHintCreate, HINT_KEYWORD_NOBITMAPSCAN},
{HINT_NOTIDSCAN, ScanMethodHintCreate, HINT_KEYWORD_NOTIDSCAN},
{HINT_INDEXONLYSCAN, ScanMethodHintCreate, HINT_KEYWORD_INDEXONLYSCAN},
{HINT_INDEXONLYSCANREGEXP, ScanMethodHintCreate,
HINT_KEYWORD_INDEXONLYSCANREGEXP},
{HINT_NOINDEXONLYSCAN, ScanMethodHintCreate, HINT_KEYWORD_NOINDEXONLYSCAN},
{HINT_NESTLOOP, JoinMethodHintCreate, HINT_KEYWORD_NESTLOOP},
{HINT_MERGEJOIN, JoinMethodHintCreate, HINT_KEYWORD_MERGEJOIN},
{HINT_HASHJOIN, JoinMethodHintCreate, HINT_KEYWORD_HASHJOIN},
{HINT_NONESTLOOP, JoinMethodHintCreate, HINT_KEYWORD_NONESTLOOP},
{HINT_NOMERGEJOIN, JoinMethodHintCreate, HINT_KEYWORD_NOMERGEJOIN},
{HINT_NOHASHJOIN, JoinMethodHintCreate, HINT_KEYWORD_NOHASHJOIN},
{HINT_LEADING, LeadingHintCreate, HINT_KEYWORD_LEADING},
{HINT_SET, SetHintCreate, HINT_KEYWORD_SET},
{HINT_ROWS, RowsHintCreate, HINT_KEYWORD_ROWS},
{HINT_PARALLEL, ParallelHintCreate, HINT_KEYWORD_PARALLEL},
{NULL, NULL, HINT_KEYWORD_UNRECOGNIZED}
};
PLpgSQL_plugin plugin_funcs = {
NULL,
NULL,
NULL,
pg_hint_plan_plpgsql_stmt_beg,
pg_hint_plan_plpgsql_stmt_end,
NULL,
NULL,
};
/*
* pg_hint_ExecutorEnd
*
* Force a hint to be retrieved when we are at the top of a PL recursion
* level. This can become necessary to handle hints in queries executed
* in the extended protocol, where the executor can be executed multiple
* times in a portal, but it could be possible to fail the hint retrieval.
*/
static void
pg_hint_ExecutorEnd(QueryDesc *queryDesc)
{
if (plpgsql_recurse_level <= 0)
current_hint_retrieved = false;
if (prev_ExecutorEnd)
prev_ExecutorEnd(queryDesc);
else
standard_ExecutorEnd(queryDesc);
}
/*
* Module load callbacks
*/
void
_PG_init(void)
{
PLpgSQL_plugin **var_ptr;
/* Define custom GUC variables. */
DefineCustomBoolVariable("pg_hint_plan.enable_hint",
"Force planner to use plans specified in the hint comment preceding to the query.",
NULL,
&pg_hint_plan_enable_hint,
true,
PGC_USERSET,
0,
NULL,
NULL,
NULL);
DefineCustomEnumVariable("pg_hint_plan.debug_print",
"Logs results of hint parsing.",
NULL,
&debug_level,
false,
parse_debug_level_options,
PGC_USERSET,
0,
NULL,
NULL,
NULL);
DefineCustomEnumVariable("pg_hint_plan.parse_messages",
"Message level of parse errors.",
NULL,
&pg_hint_plan_parse_message_level,
INFO,
parse_messages_level_options,
PGC_USERSET,
0,
NULL,
NULL,
NULL);
DefineCustomEnumVariable("pg_hint_plan.message_level",
"Message level of debug messages.",
NULL,
&pg_hint_plan_debug_message_level,
LOG,
parse_messages_level_options,
PGC_USERSET,
0,
NULL,
NULL,
NULL);
DefineCustomBoolVariable("pg_hint_plan.enable_hint_table",
"Let pg_hint_plan look up the hint table.",
NULL,
&pg_hint_plan_enable_hint_table,
false,
PGC_USERSET,
0,
NULL,
NULL,
NULL);
EmitWarningsOnPlaceholders("pg_hint_plan");
/* Install hooks. */
prev_post_parse_analyze_hook = post_parse_analyze_hook;
post_parse_analyze_hook = pg_hint_plan_post_parse_analyze; /* call get_current_hint_string get the hint string */
prev_planner = planner_hook;
planner_hook = pg_hint_plan_planner; /* get the hint string in sql, decided hints */
prev_join_search = join_search_hook;
join_search_hook = pg_hint_plan_join_search;
prev_set_rel_pathlist = set_rel_pathlist_hook;
set_rel_pathlist_hook = pg_hint_plan_set_rel_pathlist;
prev_ProcessUtility_hook = ProcessUtility_hook;
ProcessUtility_hook = pg_hint_plan_ProcessUtility;
prev_ExecutorEnd = ExecutorEnd_hook;
ExecutorEnd_hook = pg_hint_ExecutorEnd;
prev_make_join_rel_hook = make_join_rel_hook;
make_join_rel_hook = pg_hint_plan_make_join_rel;
prev_add_paths_to_joinrel_hook = add_paths_to_joinrel_hook;
add_paths_to_joinrel_hook = pg_hint_plan_add_paths_to_joinrel;
#ifdef USE_ORCA
prev_plan_hint_hook = plan_hint_hook;
plan_hint_hook = external_plan_hint_hook;
#endif
/* setup PL/pgSQL plugin hook */
var_ptr = (PLpgSQL_plugin **) find_rendezvous_variable("PLpgSQL_plugin");
*var_ptr = &plugin_funcs;
RegisterResourceReleaseCallback(plpgsql_query_erase_callback, NULL);
}
/*
* Module unload callback
* XXX never called
*/
void
_PG_fini(void)
{
PLpgSQL_plugin **var_ptr;
/* Uninstall hooks. */
post_parse_analyze_hook = prev_post_parse_analyze_hook;
planner_hook = prev_planner;
join_search_hook = prev_join_search;
set_rel_pathlist_hook = prev_set_rel_pathlist;
ProcessUtility_hook = prev_ProcessUtility_hook;
ExecutorEnd_hook = prev_ExecutorEnd;
make_join_rel_hook = prev_make_join_rel_hook;
add_paths_to_joinrel_hook = prev_add_paths_to_joinrel_hook;
#ifdef USE_ORCA
plan_hint_hook = prev_plan_hint_hook;
#endif
/* uninstall PL/pgSQL plugin hook */
var_ptr = (PLpgSQL_plugin **) find_rendezvous_variable("PLpgSQL_plugin");
*var_ptr = NULL;
}
/*
* create and delete functions the hint object
*/
static Hint *
ScanMethodHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword)
{
ScanMethodHint *hint;
hint = palloc(sizeof(ScanMethodHint));
hint->base.hint_str = hint_str;
hint->base.keyword = keyword;
hint->base.hint_keyword = hint_keyword;
hint->base.type = HINT_TYPE_SCAN_METHOD;
hint->base.state = HINT_STATE_NOTUSED;
hint->base.delete_func = (HintDeleteFunction) ScanMethodHintDelete;
hint->base.desc_func = (HintDescFunction) ScanMethodHintDesc;
hint->base.cmp_func = (HintCmpFunction) ScanMethodHintCmp;
hint->base.parse_func = (HintParseFunction) ScanMethodHintParse;
hint->relname = NULL;
hint->indexnames = NIL;
hint->regexp = false;
hint->enforce_mask = 0;
return (Hint *) hint;
}
static void
ScanMethodHintDelete(ScanMethodHint *hint)
{
if (!hint)
return;
if (hint->relname)
pfree(hint->relname);
list_free_deep(hint->indexnames);
pfree(hint);
}
static Hint *
JoinMethodHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword)
{
JoinMethodHint *hint;
hint = palloc(sizeof(JoinMethodHint));
hint->base.hint_str = hint_str;
hint->base.keyword = keyword;
hint->base.hint_keyword = hint_keyword;
hint->base.type = HINT_TYPE_JOIN_METHOD;
hint->base.state = HINT_STATE_NOTUSED;
hint->base.delete_func = (HintDeleteFunction) JoinMethodHintDelete;
hint->base.desc_func = (HintDescFunction) JoinMethodHintDesc;
hint->base.cmp_func = (HintCmpFunction) JoinMethodHintCmp;
hint->base.parse_func = (HintParseFunction) JoinMethodHintParse;
hint->nrels = 0;
hint->inner_nrels = 0;
hint->relnames = NULL;
hint->enforce_mask = 0;
hint->joinrelids = NULL;
hint->inner_joinrelids = NULL;
return (Hint *) hint;
}
static void
JoinMethodHintDelete(JoinMethodHint *hint)
{
if (!hint)
return;
if (hint->relnames)
{
int i;
for (i = 0; i < hint->nrels; i++)
pfree(hint->relnames[i]);
pfree(hint->relnames);
}
bms_free(hint->joinrelids);
bms_free(hint->inner_joinrelids);
pfree(hint);
}
static Hint *
LeadingHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword)
{
LeadingHint *hint;
hint = palloc(sizeof(LeadingHint));
hint->base.hint_str = hint_str;
hint->base.keyword = keyword;
hint->base.hint_keyword = hint_keyword;
hint->base.type = HINT_TYPE_LEADING;
hint->base.state = HINT_STATE_NOTUSED;
hint->base.delete_func = (HintDeleteFunction)LeadingHintDelete;
hint->base.desc_func = (HintDescFunction) LeadingHintDesc;
hint->base.cmp_func = (HintCmpFunction) LeadingHintCmp;
hint->base.parse_func = (HintParseFunction) LeadingHintParse;
hint->relations = NIL;
hint->outer_inner = NULL;
return (Hint *) hint;
}
static void
LeadingHintDelete(LeadingHint *hint)
{
if (!hint)
return;
list_free_deep(hint->relations);
if (hint->outer_inner)
pfree(hint->outer_inner);
pfree(hint);
}
static Hint *
SetHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword)
{
SetHint *hint;
hint = palloc(sizeof(SetHint));
hint->base.hint_str = hint_str;
hint->base.keyword = keyword;
hint->base.hint_keyword = hint_keyword;
hint->base.type = HINT_TYPE_SET;
hint->base.state = HINT_STATE_NOTUSED;
hint->base.delete_func = (HintDeleteFunction) SetHintDelete;
hint->base.desc_func = (HintDescFunction) SetHintDesc;
hint->base.cmp_func = (HintCmpFunction) SetHintCmp;
hint->base.parse_func = (HintParseFunction) SetHintParse;
hint->name = NULL;
hint->value = NULL;
hint->words = NIL;
return (Hint *) hint;
}
static void
SetHintDelete(SetHint *hint)
{
if (!hint)
return;
if (hint->name)
pfree(hint->name);
if (hint->value)
pfree(hint->value);
if (hint->words)
list_free(hint->words);
pfree(hint);
}
static Hint *
RowsHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword)
{
RowsHint *hint;
hint = palloc(sizeof(RowsHint));
hint->base.hint_str = hint_str;
hint->base.keyword = keyword;
hint->base.hint_keyword = hint_keyword;
hint->base.type = HINT_TYPE_ROWS;
hint->base.state = HINT_STATE_NOTUSED;
hint->base.delete_func = (HintDeleteFunction) RowsHintDelete;
hint->base.desc_func = (HintDescFunction) RowsHintDesc;
hint->base.cmp_func = (HintCmpFunction) RowsHintCmp;
hint->base.parse_func = (HintParseFunction) RowsHintParse;
hint->nrels = 0;
hint->inner_nrels = 0;
hint->relnames = NULL;
hint->joinrelids = NULL;
hint->inner_joinrelids = NULL;
hint->rows_str = NULL;
hint->value_type = RVT_ABSOLUTE;
hint->rows = 0;
return (Hint *) hint;
}
static void
RowsHintDelete(RowsHint *hint)
{
if (!hint)
return;
if (hint->relnames)
{
int i;
for (i = 0; i < hint->nrels; i++)
pfree(hint->relnames[i]);
pfree(hint->relnames);
}
bms_free(hint->joinrelids);
bms_free(hint->inner_joinrelids);
pfree(hint);
}
static Hint *
ParallelHintCreate(const char *hint_str, const char *keyword,
HintKeyword hint_keyword)
{
ParallelHint *hint;
hint = palloc(sizeof(ParallelHint));
hint->base.hint_str = hint_str;
hint->base.keyword = keyword;
hint->base.hint_keyword = hint_keyword;
hint->base.type = HINT_TYPE_PARALLEL;
hint->base.state = HINT_STATE_NOTUSED;
hint->base.delete_func = (HintDeleteFunction) ParallelHintDelete;
hint->base.desc_func = (HintDescFunction) ParallelHintDesc;
hint->base.cmp_func = (HintCmpFunction) ParallelHintCmp;
hint->base.parse_func = (HintParseFunction) ParallelHintParse;
hint->relname = NULL;
hint->nworkers = 0;
hint->nworkers_str = "0";
return (Hint *) hint;
}
static void
ParallelHintDelete(ParallelHint *hint)
{
if (!hint)
return;
if (hint->relname)
pfree(hint->relname);
pfree(hint);
}
static HintState *
HintStateCreate(void)
{
HintState *hstate;
hstate = palloc(sizeof(HintState));
hstate->hint_str = NULL;
hstate->nall_hints = 0;
hstate->max_all_hints = 0;
hstate->all_hints = NULL;
memset(hstate->num_hints, 0, sizeof(hstate->num_hints));
hstate->scan_hints = NULL;
hstate->init_scan_mask = 0;
hstate->init_nworkers = 0;
hstate->init_min_para_tablescan_size = 0;
hstate->init_min_para_indexscan_size = 0;
hstate->init_paratup_cost = 0;
hstate->init_parasetup_cost = 0;
hstate->current_root = NULL;
hstate->parent_relid = 0;
hstate->parent_scan_hint = NULL;
hstate->parent_parallel_hint = NULL;
hstate->parent_index_infos = NIL;
hstate->join_hints = NULL;
hstate->init_join_mask = 0;
hstate->join_hint_level = NULL;
hstate->leading_hint = NULL;
hstate->context = superuser() ? PGC_SUSET : PGC_USERSET;
hstate->set_hints = NULL;
hstate->rows_hints = NULL;
hstate->parallel_hints = NULL;
hstate->log_level = 0;
return hstate;
}
static void
HintStateDelete(HintState *hstate)
{
int i;
if (!hstate)
return;
if (hstate->hint_str)
pfree(hstate->hint_str);
for (i = 0; i < hstate->nall_hints ; i++)
hstate->all_hints[i]->delete_func(hstate->all_hints[i]);
if (hstate->all_hints)
pfree(hstate->all_hints);
if (hstate->parent_index_infos)
list_free(hstate->parent_index_infos);
/*
* We have another few or dozen of palloced block in the struct, but don't
* bother completely clean up all of them since they will be cleaned-up at
* the end of this query.
*/
}
/*
* Copy given value into buf, with quoting with '"' if necessary.
*/
static void
quote_value(StringInfo buf, const char *value)
{
bool need_quote = false;
const char *str;
for (str = value; *str != '\0'; str++)
{
if (isspace(*str) || *str == '(' || *str == ')' || *str == '"')
{
need_quote = true;
appendStringInfoCharMacro(buf, '"');
break;
}
}
for (str = value; *str != '\0'; str++)
{
if (*str == '"')
appendStringInfoCharMacro(buf, '"');
appendStringInfoCharMacro(buf, *str);
}
if (need_quote)
appendStringInfoCharMacro(buf, '"');
}
static void
ScanMethodHintDesc(ScanMethodHint *hint, StringInfo buf, bool nolf)
{
ListCell *l;
appendStringInfo(buf, "%s(", hint->base.keyword);
if (hint->relname != NULL)
{
quote_value(buf, hint->relname);
foreach(l, hint->indexnames)
{
appendStringInfoCharMacro(buf, ' ');
quote_value(buf, (char *) lfirst(l));
}
}
appendStringInfoString(buf, ")");
if (!nolf)
appendStringInfoChar(buf, '\n');
}
static void
JoinMethodHintDesc(JoinMethodHint *hint, StringInfo buf, bool nolf)
{
int i;
appendStringInfo(buf, "%s(", hint->base.keyword);
if (hint->relnames != NULL)
{
quote_value(buf, hint->relnames[0]);
for (i = 1; i < hint->nrels; i++)
{
appendStringInfoCharMacro(buf, ' ');
quote_value(buf, hint->relnames[i]);
}
}
appendStringInfoString(buf, ")");
if (!nolf)
appendStringInfoChar(buf, '\n');
}
static void
OuterInnerDesc(OuterInnerRels *outer_inner, StringInfo buf)
{
if (outer_inner->relation == NULL)
{
bool is_first;
ListCell *l;
is_first = true;
appendStringInfoCharMacro(buf, '(');
foreach(l, outer_inner->outer_inner_pair)
{
if (is_first)
is_first = false;
else
appendStringInfoCharMacro(buf, ' ');
OuterInnerDesc(lfirst(l), buf);
}
appendStringInfoCharMacro(buf, ')');
}
else
quote_value(buf, outer_inner->relation);
}
static void
LeadingHintDesc(LeadingHint *hint, StringInfo buf, bool nolf)
{
appendStringInfo(buf, "%s(", HINT_LEADING);
if (hint->outer_inner == NULL)
{
ListCell *l;
bool is_first;
is_first = true;
foreach(l, hint->relations)
{
if (is_first)
is_first = false;
else
appendStringInfoCharMacro(buf, ' ');
quote_value(buf, (char *) lfirst(l));
}
}
else
OuterInnerDesc(hint->outer_inner, buf);
appendStringInfoString(buf, ")");
if (!nolf)
appendStringInfoChar(buf, '\n');
}
static void
SetHintDesc(SetHint *hint, StringInfo buf, bool nolf)
{
bool is_first = true;
ListCell *l;
appendStringInfo(buf, "%s(", HINT_SET);
foreach(l, hint->words)
{
if (is_first)
is_first = false;
else
appendStringInfoCharMacro(buf, ' ');
quote_value(buf, (char *) lfirst(l));
}
appendStringInfo(buf, ")");
if (!nolf)
appendStringInfoChar(buf, '\n');
}
static void
RowsHintDesc(RowsHint *hint, StringInfo buf, bool nolf)
{
int i;
appendStringInfo(buf, "%s(", hint->base.keyword);
if (hint->relnames != NULL)
{
quote_value(buf, hint->relnames[0]);
for (i = 1; i < hint->nrels; i++)
{
appendStringInfoCharMacro(buf, ' ');
quote_value(buf, hint->relnames[i]);
}
}
if (hint->rows_str != NULL)
appendStringInfo(buf, " %s", hint->rows_str);
appendStringInfoString(buf, ")");
if (!nolf)
appendStringInfoChar(buf, '\n');
}
static void
ParallelHintDesc(ParallelHint *hint, StringInfo buf, bool nolf)
{
appendStringInfo(buf, "%s(", hint->base.keyword);
if (hint->relname != NULL)
{
quote_value(buf, hint->relname);
/* number of workers */
appendStringInfoCharMacro(buf, ' ');
quote_value(buf, hint->nworkers_str);
/* application mode of num of workers */
appendStringInfoCharMacro(buf, ' ');
appendStringInfoString(buf,
(hint->force_parallel ? "hard" : "soft"));
}
appendStringInfoString(buf, ")");
if (!nolf)
appendStringInfoChar(buf, '\n');
}
/*
* Append string which represents all hints in a given state to buf, with
* preceding title with them.
*/
static void
desc_hint_in_state(HintState *hstate, StringInfo buf, const char *title,
HintStatus state, bool nolf)
{
int i, nshown;
appendStringInfo(buf, "%s:", title);
if (!nolf)
appendStringInfoChar(buf, '\n');
nshown = 0;
for (i = 0; i < hstate->nall_hints; i++)
{
if (hstate->all_hints[i]->state != state)
continue;
hstate->all_hints[i]->desc_func(hstate->all_hints[i], buf, nolf);
nshown++;
}
if (nolf && nshown == 0)
appendStringInfoString(buf, "(none)");
}
/*
* Dump contents of given hstate to server log with log level LOG.
*/
static void
HintStateDump(HintState *hstate)
{
StringInfoData buf;
if (!hstate)
{
elog(pg_hint_plan_debug_message_level, "pg_hint_plan:\nno hint");
return;
}
initStringInfo(&buf);
appendStringInfoString(&buf, "pg_hint_plan:\n");
desc_hint_in_state(hstate, &buf, "used hint", HINT_STATE_USED, false);
desc_hint_in_state(hstate, &buf, "not used hint", HINT_STATE_NOTUSED, false);
desc_hint_in_state(hstate, &buf, "duplication hint", HINT_STATE_DUPLICATION, false);
desc_hint_in_state(hstate, &buf, "error hint", HINT_STATE_ERROR, false);
ereport(pg_hint_plan_debug_message_level,
(errmsg ("%s", buf.data)));
pfree(buf.data);
}
static void
HintStateDump2(HintState *hstate)
{
StringInfoData buf;
if (!hstate)
{
elog(pg_hint_plan_debug_message_level,
"pg_hint_plan%s: HintStateDump: no hint", qnostr);
return;
}
initStringInfo(&buf);
appendStringInfo(&buf, "pg_hint_plan%s: HintStateDump: ", qnostr);
desc_hint_in_state(hstate, &buf, "{used hints", HINT_STATE_USED, true);
desc_hint_in_state(hstate, &buf, "}, {not used hints", HINT_STATE_NOTUSED, true);
desc_hint_in_state(hstate, &buf, "}, {duplicate hints", HINT_STATE_DUPLICATION, true);
desc_hint_in_state(hstate, &buf, "}, {error hints", HINT_STATE_ERROR, true);
appendStringInfoChar(&buf, '}');
ereport(pg_hint_plan_debug_message_level,
(errmsg("%s", buf.data),
errhidestmt(true),
errhidecontext(true)));
pfree(buf.data);
}
/*
* compare functions
*/
static int
RelnameCmp(const void *a, const void *b)
{
const char *relnamea = *((const char **) a);
const char *relnameb = *((const char **) b);
return strcmp(relnamea, relnameb);
}
static int
ScanMethodHintCmp(const ScanMethodHint *a, const ScanMethodHint *b)
{
return RelnameCmp(&a->relname, &b->relname);
}
static int
JoinMethodHintCmp(const JoinMethodHint *a, const JoinMethodHint *b)
{
int i;
if (a->nrels != b->nrels)
return a->nrels - b->nrels;
for (i = 0; i < a->nrels; i++)
{
int result;
if ((result = RelnameCmp(&a->relnames[i], &b->relnames[i])) != 0)
return result;
}
return 0;
}
static int
LeadingHintCmp(const LeadingHint *a, const LeadingHint *b)
{
return 0;
}
static int
SetHintCmp(const SetHint *a, const SetHint *b)
{
return strcmp(a->name, b->name);
}
static int
RowsHintCmp(const RowsHint *a, const RowsHint *b)
{
int i;
if (a->nrels != b->nrels)
return a->nrels - b->nrels;
for (i = 0; i < a->nrels; i++)
{
int result;
if ((result = RelnameCmp(&a->relnames[i], &b->relnames[i])) != 0)
return result;
}
return 0;
}
static int
ParallelHintCmp(const ParallelHint *a, const ParallelHint *b)
{
return RelnameCmp(&a->relname, &b->relname);
}
static int
HintCmp(const void *a, const void *b)
{
const Hint *hinta = *((const Hint **) a);
const Hint *hintb = *((const Hint **) b);
if (hinta->type != hintb->type)
return hinta->type - hintb->type;
if (hinta->state == HINT_STATE_ERROR)
return -1;
if (hintb->state == HINT_STATE_ERROR)
return 1;
return hinta->cmp_func(hinta, hintb);
}
/*
* Returns byte offset of hint b from hint a. If hint a was specified before
* b, positive value is returned.
*/
static int
HintCmpWithPos(const void *a, const void *b)
{
const Hint *hinta = *((const Hint **) a);
const Hint *hintb = *((const Hint **) b);
int result;
result = HintCmp(a, b);
if (result == 0)
result = hinta->hint_str - hintb->hint_str;
return result;
}
/*
* parse functions
*/
static const char *
parse_keyword(const char *str, StringInfo buf)
{
skip_space(str);
while (!isspace(*str) && *str != '(' && *str != '\0')
appendStringInfoCharMacro(buf, *str++);
return str;
}
static const char *
skip_parenthesis(const char *str, char parenthesis)
{
skip_space(str);
if (*str != parenthesis)
{
if (parenthesis == '(')
hint_ereport(str, ("Opening parenthesis is necessary."));
else if (parenthesis == ')')
hint_ereport(str, ("Closing parenthesis is necessary."));
return NULL;
}
str++;
return str;
}
/*
* Parse a token from str, and store malloc'd copy into word. A token can be
* quoted with '"'. Return value is pointer to unparsed portion of original
* string, or NULL if an error occurred.
*
* Parsed token is truncated within NAMEDATALEN-1 bytes, when truncate is true.
*/
static const char *
parse_quoted_value(const char *str, char **word, bool truncate)
{
StringInfoData buf;
bool in_quote;
/* Skip leading spaces. */
skip_space(str);
initStringInfo(&buf);
if (*str == '"')
{
str++;
in_quote = true;
}
else
in_quote = false;
while (true)
{
if (in_quote)
{
/* Double quotation must be closed. */
if (*str == '\0')
{
pfree(buf.data);
hint_ereport(str, ("Unterminated quoted string."));
return NULL;
}
/*
* Skip escaped double quotation.
*
* We don't allow slash-asterisk and asterisk-slash (delimiters of
* block comments) to be an object name, so users must specify
* alias for such object names.
*
* Those special names can be allowed if we care escaped slashes
* and asterisks, but we don't.
*/
if (*str == '"')
{
str++;
if (*str != '"')
break;
}
}
else if (isspace(*str) || *str == '(' || *str == ')' || *str == '"' ||
*str == '\0')
break;
appendStringInfoCharMacro(&buf, *str++);
}
if (buf.len == 0)
{
hint_ereport(str, ("Zero-length delimited string."));
pfree(buf.data);
return NULL;
}
/* Truncate name if it's too long */
if (truncate)
truncate_identifier(buf.data, strlen(buf.data), true);
*word = buf.data;
return str;
}
static OuterInnerRels *
OuterInnerRelsCreate(char *name, List *outer_inner_list)
{
OuterInnerRels *outer_inner;
outer_inner = palloc(sizeof(OuterInnerRels));
outer_inner->relation = name;
outer_inner->outer_inner_pair = outer_inner_list;
return outer_inner;
}
static const char *
parse_parentheses_Leading_in(const char *str, OuterInnerRels **outer_inner)
{
List *outer_inner_pair = NIL;
if ((str = skip_parenthesis(str, '(')) == NULL)
return NULL;
skip_space(str);
/* Store words in parentheses into outer_inner_list. */
while(*str != ')' && *str != '\0')
{
OuterInnerRels *outer_inner_rels;
if (*str == '(')
{
str = parse_parentheses_Leading_in(str, &outer_inner_rels);
if (str == NULL)
break;
}
else
{
char *name;
if ((str = parse_quoted_value(str, &name, true)) == NULL)
break;
else
outer_inner_rels = OuterInnerRelsCreate(name, NIL);
}
outer_inner_pair = lappend(outer_inner_pair, outer_inner_rels);
skip_space(str);
}
if (str == NULL ||
(str = skip_parenthesis(str, ')')) == NULL)
{
list_free(outer_inner_pair);
return NULL;
}
*outer_inner = OuterInnerRelsCreate(NULL, outer_inner_pair);
return str;
}
static const char *
parse_parentheses_Leading(const char *str, List **name_list,
OuterInnerRels **outer_inner)
{
char *name;
bool truncate = true;
if ((str = skip_parenthesis(str, '(')) == NULL)
return NULL;
skip_space(str);
if (*str =='(')
{
if ((str = parse_parentheses_Leading_in(str, outer_inner)) == NULL)
return NULL;
}
else
{
/* Store words in parentheses into name_list. */
while(*str != ')' && *str != '\0')
{
if ((str = parse_quoted_value(str, &name, truncate)) == NULL)
{
list_free(*name_list);
return NULL;
}
*name_list = lappend(*name_list, name);
skip_space(str);
}
}
if ((str = skip_parenthesis(str, ')')) == NULL)
return NULL;
return str;
}
static const char *
parse_parentheses(const char *str, List **name_list, HintKeyword keyword)
{
char *name;
bool truncate = true;
if ((str = skip_parenthesis(str, '(')) == NULL)
return NULL;
skip_space(str);
/* Store words in parentheses into name_list. */
while(*str != ')' && *str != '\0')
{
if ((str = parse_quoted_value(str, &name, truncate)) == NULL)
{
list_free(*name_list);
return NULL;
}
*name_list = lappend(*name_list, name);
skip_space(str);
if (keyword == HINT_KEYWORD_INDEXSCANREGEXP ||
keyword == HINT_KEYWORD_INDEXONLYSCANREGEXP ||
keyword == HINT_KEYWORD_BITMAPSCANREGEXP ||
keyword == HINT_KEYWORD_SET)
{
truncate = false;
}
}
if ((str = skip_parenthesis(str, ')')) == NULL)
return NULL;
return str;
}
static void
parse_hints(HintState *hstate, Query *parse, const char *str)
{
StringInfoData buf;
char *head;
initStringInfo(&buf);
while (*str != '\0')
{
const HintParser *parser;
/* in error message, we output the comment including the keyword. */
head = (char *) str;
/* parse only the keyword of the hint. */
resetStringInfo(&buf);
str = parse_keyword(str, &buf);
for (parser = parsers; parser->keyword != NULL; parser++)
{
char *keyword = parser->keyword;
Hint *hint;
if (pg_strcasecmp(buf.data, keyword) != 0)
continue;
hint = parser->create_func(head, keyword, parser->hint_keyword);
/* parser of each hint does parse in a parenthesis. */
if ((str = hint->parse_func(hint, hstate, parse, str)) == NULL)
{
hint->delete_func(hint);
pfree(buf.data);
return;
}
/*
* Add hint information into all_hints array. If we don't have
* enough space, double the array.
*/
if (hstate->nall_hints == 0)
{
hstate->max_all_hints = HINT_ARRAY_DEFAULT_INITSIZE;
hstate->all_hints = (Hint **)
palloc(sizeof(Hint *) * hstate->max_all_hints);
}
else if (hstate->nall_hints == hstate->max_all_hints)
{
hstate->max_all_hints *= 2;
hstate->all_hints = (Hint **)
repalloc(hstate->all_hints,
sizeof(Hint *) * hstate->max_all_hints);
}
hstate->all_hints[hstate->nall_hints] = hint;
hstate->nall_hints++;
skip_space(str);
break;
}
if (parser->keyword == NULL)
{
hint_ereport(head,
("Unrecognized hint keyword \"%s\".", buf.data));
pfree(buf.data);
return;
}
}
pfree(buf.data);
}
/*
* Get hints from table by client-supplied query string and application name.
*/
static const char *
get_hints_from_table(const char *client_query, const char *client_application)
{
const char *search_query =
"SELECT hints "
" FROM hint_plan.hints "
" WHERE norm_query_string = $1 "
" AND ( application_name = $2 "
" OR application_name = '' ) "
" ORDER BY application_name DESC";
static SPIPlanPtr plan = NULL;
char *hints = NULL;
Oid argtypes[2] = { TEXTOID, TEXTOID };
Datum values[2];
char nulls[2] = {' ', ' '};
text *qry;
text *app;
PG_TRY();
{
bool snapshot_set = false;
hint_inhibit_level++;
if (!ActiveSnapshotSet())
{
PushActiveSnapshot(GetTransactionSnapshot());
snapshot_set = true;
}
SPI_connect();
if (plan == NULL)
{
SPIPlanPtr p;
p = SPI_prepare(search_query, 2, argtypes);
plan = SPI_saveplan(p);
SPI_freeplan(p);
}
qry = cstring_to_text(client_query);
app = cstring_to_text(client_application);
values[0] = PointerGetDatum(qry);
values[1] = PointerGetDatum(app);
SPI_execute_plan(plan, values, nulls, true, 1);
if (SPI_processed > 0)
{
char *buf;
hints = SPI_getvalue(SPI_tuptable->vals[0],
SPI_tuptable->tupdesc, 1);
/*
* Here we use SPI_palloc to ensure that hints string is valid even
* after SPI_finish call. We can't use simple palloc because it
* allocates memory in SPI's context and that context is deleted in
* SPI_finish.
*/
buf = SPI_palloc(strlen(hints) + 1);
strcpy(buf, hints);
hints = buf;
}
SPI_finish();
if (snapshot_set)
PopActiveSnapshot();
hint_inhibit_level--;
}
PG_CATCH();
{
hint_inhibit_level--;
PG_RE_THROW();
}
PG_END_TRY();
return hints;
}
/*
* Get client-supplied query string. Addtion to that the jumbled query is
* supplied if the caller requested. From the restriction of PGHintPlanJumbleQuery, some
* kind of query needs special amendments. Reutrns NULL if this query doesn't
* change the current hint. This function returns NULL also when something
* wrong has happend and let the caller continue using the current hints.
*/
static const char *
get_query_string(ParseState *pstate, Query *query, Query **jumblequery)
{
const char *p = debug_query_string;
/*
* If debug_query_string is set, it is the top level statement. But in some
* cases we reach here with debug_query_string set NULL for example in the
* case of DESCRIBE message handling or EXECUTE command. We may still see a
* candidate top-level query in pstate in the case.
*/
if (pstate && pstate->p_sourcetext)
p = pstate->p_sourcetext;
/* We don't see a query string, return NULL */
if (!p)
return NULL;
if (jumblequery != NULL)
*jumblequery = query;
if (query->commandType == CMD_UTILITY)
{
Query *target_query = (Query *)query->utilityStmt;
/*
* Some CMD_UTILITY statements have a subquery that we can hint on.
* Since EXPLAIN can be placed before other kind of utility statements
* and EXECUTE can be contained other kind of utility statements, these
* conditions are not mutually exclusive and should be considered in
* this order.
*/
if (IsA(target_query, ExplainStmt))
{
ExplainStmt *stmt = (ExplainStmt *)target_query;
Assert(IsA(stmt->query, Query));
target_query = (Query *)stmt->query;
/* strip out the top-level query for further processing */
if (target_query->commandType == CMD_UTILITY &&
target_query->utilityStmt != NULL)
target_query = (Query *)target_query->utilityStmt;
}
if (IsA(target_query, DeclareCursorStmt))
{
DeclareCursorStmt *stmt = (DeclareCursorStmt *)target_query;
Query *query = (Query *)stmt->query;
/* the target must be CMD_SELECT in this case */
Assert(IsA(query, Query) && query->commandType == CMD_SELECT);
target_query = query;
}
if (IsA(target_query, CreateTableAsStmt))
{
CreateTableAsStmt *stmt = (CreateTableAsStmt *) target_query;
Assert(IsA(stmt->query, Query));
target_query = (Query *) stmt->query;
/* strip out the top-level query for further processing */
if (target_query->commandType == CMD_UTILITY &&
target_query->utilityStmt != NULL)
target_query = (Query *)target_query->utilityStmt;
}
if (IsA(target_query, ExecuteStmt))
{
/*
* Use the prepared query for EXECUTE. The Query for jumble
* also replaced with the corresponding one.
*/
ExecuteStmt *stmt = (ExecuteStmt *)target_query;
PreparedStatement *entry;
/*
* Silently ignore nonexistent prepared statements. This may happen
* for EXECUTE within a function definition. Otherwise the
* execution will fail anyway.
*/
entry = FetchPreparedStatement(stmt->name, false);
if (entry && entry->plansource->is_valid)
{
p = entry->plansource->query_string;
target_query = (Query *) linitial (entry->plansource->query_list);
}
else
{
/* igonre the hint for EXECUTE if invalidated */
p = NULL;
target_query = NULL;
}
}
/* PGHintPlanJumbleQuery accespts only a non-utility Query */
if (target_query &&
(!IsA(target_query, Query) ||
target_query->utilityStmt != NULL))
target_query = NULL;
if (jumblequery)
*jumblequery = target_query;
}
/*
* Return NULL if pstate is not of top-level query. We don't need this
* when jumble info is not requested or cannot do this when pstate is NULL.
*/
else if (!jumblequery && pstate && pstate->p_sourcetext != p &&
strcmp(pstate->p_sourcetext, p) != 0)
p = NULL;
return p;
}
/*
* Get hints from the head block comment in client-supplied query string.
*/
static const char *
get_hints_from_comment(const char *p)
{
const char *hint_head;
char *head;
char *tail;
int len;
if (p == NULL)
return NULL;
/* extract query head comment. */
hint_head = strstr(p, HINT_START);
if (hint_head == NULL)
return NULL;
for (;p < hint_head; p++)
{
/*
* Allow these characters precedes hint comment:
* - digits
* - alphabets which are in ASCII range
* - space, tabs and new-lines
* - underscores, for identifier
* - commas, for SELECT clause, EXPLAIN and PREPARE
* - parentheses, for EXPLAIN and PREPARE
*
* Note that we don't use isalpha() nor isalnum() in ctype.h here to
* avoid behavior which depends on locale setting.
*/
if (!(*p >= '0' && *p <= '9') &&
!(*p >= 'A' && *p <= 'Z') &&
!(*p >= 'a' && *p <= 'z') &&
!isspace(*p) &&
*p != '_' &&
*p != ',' &&
*p != '(' && *p != ')')
return NULL;
}
len = strlen(HINT_START);
head = (char *) p;
p += len;
skip_space(p);
/* find hint end keyword. */
if ((tail = strstr(p, HINT_END)) == NULL)
{
hint_ereport(head, ("Unterminated block comment."));
return NULL;
}
/* We don't support nested block comments. */
if ((head = strstr(p, BLOCK_COMMENT_START)) != NULL && head < tail)
{
hint_ereport(head, ("Nested block comments are not supported."));
return NULL;
}
/* Make a copy of hint. */
len = tail - p;
head = palloc(len + 1);
memcpy(head, p, len);
head[len] = '\0';
p = head;
return p;
}
/*
* Parse hints that got, create hint struct from parse tree and parse hints.
*/
static HintState *
create_hintstate(Query *parse, const char *hints)
{
const char *p;
int i;
HintState *hstate;
if (hints == NULL)
return NULL;
/* -1 means that no Parallel hint is specified. */
max_hint_nworkers = -1;
p = hints;
hstate = HintStateCreate();
hstate->hint_str = (char *) hints;
/* parse each hint. */
parse_hints(hstate, parse, p);
/* When nothing specified a hint, we free HintState and returns NULL. */
if (hstate->nall_hints == 0)
{
HintStateDelete(hstate);
return NULL;
}
/* Sort hints in order of original position. */
qsort(hstate->all_hints, hstate->nall_hints, sizeof(Hint *),
HintCmpWithPos);
/* Count number of hints per hint-type. */
for (i = 0; i < hstate->nall_hints; i++)
{
Hint *cur_hint = hstate->all_hints[i];
hstate->num_hints[cur_hint->type]++;
}
/*
* If an object (or a set of objects) has multiple hints of same hint-type,
* only the last hint is valid and others are ignored in planning.
* Hints except the last are marked as 'duplicated' to remember the order.
*/
for (i = 0; i < hstate->nall_hints - 1; i++)
{
Hint *cur_hint = hstate->all_hints[i];
Hint *next_hint = hstate->all_hints[i + 1];
/*
* Leading hint is marked as 'duplicated' in transform_join_hints.
*/
if (cur_hint->type == HINT_TYPE_LEADING &&
next_hint->type == HINT_TYPE_LEADING)
continue;
/*
* Note that we need to pass addresses of hint pointers, because
* HintCmp is designed to sort array of Hint* by qsort.
*/
if (HintCmp(&cur_hint, &next_hint) == 0)
{
hint_ereport(cur_hint->hint_str,
("Conflict %s hint.", HintTypeName[cur_hint->type]));
cur_hint->state = HINT_STATE_DUPLICATION;
}
}
/*
* Make sure that per-type array pointers point proper position in the
* array which consists of all hints.
*/
hstate->scan_hints = (ScanMethodHint **) hstate->all_hints;
hstate->join_hints = (JoinMethodHint **) (hstate->scan_hints +
hstate->num_hints[HINT_TYPE_SCAN_METHOD]);
hstate->leading_hint = (LeadingHint **) (hstate->join_hints +
hstate->num_hints[HINT_TYPE_JOIN_METHOD]);
hstate->set_hints = (SetHint **) (hstate->leading_hint +
hstate->num_hints[HINT_TYPE_LEADING]);
hstate->rows_hints = (RowsHint **) (hstate->set_hints +
hstate->num_hints[HINT_TYPE_SET]);
hstate->parallel_hints = (ParallelHint **) (hstate->rows_hints +
hstate->num_hints[HINT_TYPE_ROWS]);
return hstate;
}
/*
* Parse inside of parentheses of scan-method hints.
*/
static const char *
ScanMethodHintParse(ScanMethodHint *hint, HintState *hstate, Query *parse,
const char *str)
{
const char *keyword = hint->base.keyword;
HintKeyword hint_keyword = hint->base.hint_keyword;
List *name_list = NIL;
int length;
if ((str = parse_parentheses(str, &name_list, hint_keyword)) == NULL)
return NULL;
/* Parse relation name and index name(s) if given hint accepts. */
length = list_length(name_list);
/* at least twp parameters required */
if (length < 1)
{
hint_ereport(str,
("%s hint requires a relation.", hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
return str;
}
hint->relname = linitial(name_list);
hint->indexnames = list_delete_first(name_list);
/* check whether the hint accepts index name(s) */
if (length > 1 && !SCAN_HINT_ACCEPTS_INDEX_NAMES(hint_keyword))
{
hint_ereport(str,
("%s hint accepts only one relation.",
hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
return str;
}
/* Set a bit for specified hint. */
switch (hint_keyword)
{
case HINT_KEYWORD_SEQSCAN:
hint->enforce_mask = ENABLE_SEQSCAN;
break;
case HINT_KEYWORD_INDEXSCAN:
hint->enforce_mask = ENABLE_INDEXSCAN;
break;
case HINT_KEYWORD_INDEXSCANREGEXP:
hint->enforce_mask = ENABLE_INDEXSCAN;
hint->regexp = true;
break;
case HINT_KEYWORD_BITMAPSCAN:
hint->enforce_mask = ENABLE_BITMAPSCAN;
break;
case HINT_KEYWORD_BITMAPSCANREGEXP:
hint->enforce_mask = ENABLE_BITMAPSCAN;
hint->regexp = true;
break;
case HINT_KEYWORD_TIDSCAN:
hint->enforce_mask = ENABLE_TIDSCAN;
break;
case HINT_KEYWORD_NOSEQSCAN:
hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_SEQSCAN;
break;
case HINT_KEYWORD_NOINDEXSCAN:
hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_INDEXSCAN;
break;
case HINT_KEYWORD_NOBITMAPSCAN:
hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_BITMAPSCAN;
break;
case HINT_KEYWORD_NOTIDSCAN:
hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_TIDSCAN;
break;
case HINT_KEYWORD_INDEXONLYSCAN:
hint->enforce_mask = ENABLE_INDEXSCAN | ENABLE_INDEXONLYSCAN;
break;
case HINT_KEYWORD_INDEXONLYSCANREGEXP:
hint->enforce_mask = ENABLE_INDEXSCAN | ENABLE_INDEXONLYSCAN;
hint->regexp = true;
break;
case HINT_KEYWORD_NOINDEXONLYSCAN:
hint->enforce_mask = ENABLE_ALL_SCAN ^ ENABLE_INDEXONLYSCAN;
break;
default:
hint_ereport(str, ("Unrecognized hint keyword \"%s\".", keyword));
return NULL;
break;
}
return str;
}
static const char *
JoinMethodHintParse(JoinMethodHint *hint, HintState *hstate, Query *parse,
const char *str)
{
const char *keyword = hint->base.keyword;
HintKeyword hint_keyword = hint->base.hint_keyword;
List *name_list = NIL;
if ((str = parse_parentheses(str, &name_list, hint_keyword)) == NULL)
return NULL;
hint->nrels = list_length(name_list);
if (hint->nrels > 0)
{
ListCell *l;
int i = 0;
/*
* Transform relation names from list to array to sort them with qsort
* after.
*/
hint->relnames = palloc(sizeof(char *) * hint->nrels);
foreach (l, name_list)
{
hint->relnames[i] = lfirst(l);
i++;
}
}
list_free(name_list);
/* A join hint requires at least two relations */
if (hint->nrels < 2)
{
hint_ereport(str,
("%s hint requires at least two relations.",
hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
return str;
}
/* Sort hints in alphabetical order of relation names. */
qsort(hint->relnames, hint->nrels, sizeof(char *), RelnameCmp);
switch (hint_keyword)
{
case HINT_KEYWORD_NESTLOOP:
hint->enforce_mask = ENABLE_NESTLOOP;
break;
case HINT_KEYWORD_MERGEJOIN:
hint->enforce_mask = ENABLE_MERGEJOIN;
break;
case HINT_KEYWORD_HASHJOIN:
hint->enforce_mask = ENABLE_HASHJOIN;
break;
case HINT_KEYWORD_NONESTLOOP:
hint->enforce_mask = ENABLE_ALL_JOIN ^ ENABLE_NESTLOOP;
break;
case HINT_KEYWORD_NOMERGEJOIN:
hint->enforce_mask = ENABLE_ALL_JOIN ^ ENABLE_MERGEJOIN;
break;
case HINT_KEYWORD_NOHASHJOIN:
hint->enforce_mask = ENABLE_ALL_JOIN ^ ENABLE_HASHJOIN;
break;
default:
hint_ereport(str, ("Unrecognized hint keyword \"%s\".", keyword));
return NULL;
break;
}
return str;
}
static bool
OuterInnerPairCheck(OuterInnerRels *outer_inner)
{
ListCell *l;
if (outer_inner->outer_inner_pair == NIL)
{
if (outer_inner->relation)
return true;
else
return false;
}
if (list_length(outer_inner->outer_inner_pair) == 2)
{
foreach(l, outer_inner->outer_inner_pair)
{
if (!OuterInnerPairCheck(lfirst(l)))
return false;
}
}
else
return false;
return true;
}
static List *
OuterInnerList(OuterInnerRels *outer_inner)
{
List *outer_inner_list = NIL;
ListCell *l;
OuterInnerRels *outer_inner_rels;
foreach(l, outer_inner->outer_inner_pair)
{
outer_inner_rels = (OuterInnerRels *)(lfirst(l));
if (outer_inner_rels->relation != NULL)
outer_inner_list = lappend(outer_inner_list,
outer_inner_rels->relation);
else
outer_inner_list = list_concat(outer_inner_list,
OuterInnerList(outer_inner_rels));
}
return outer_inner_list;
}
static const char *
LeadingHintParse(LeadingHint *hint, HintState *hstate, Query *parse,
const char *str)
{
List *name_list = NIL;
OuterInnerRels *outer_inner = NULL;
if ((str = parse_parentheses_Leading(str, &name_list, &outer_inner)) ==
NULL)
return NULL;
if (outer_inner != NULL)
name_list = OuterInnerList(outer_inner);
hint->relations = name_list;
hint->outer_inner = outer_inner;
/* A Leading hint requires at least two relations */
if ( hint->outer_inner == NULL && list_length(hint->relations) < 2)
{
hint_ereport(hint->base.hint_str,
("%s hint requires at least two relations.",
HINT_LEADING));
hint->base.state = HINT_STATE_ERROR;
}
else if (hint->outer_inner != NULL &&
!OuterInnerPairCheck(hint->outer_inner))
{
hint_ereport(hint->base.hint_str,
("%s hint requires two sets of relations when parentheses nests.",
HINT_LEADING));
hint->base.state = HINT_STATE_ERROR;
}
return str;
}
static const char *
SetHintParse(SetHint *hint, HintState *hstate, Query *parse, const char *str)
{
List *name_list = NIL;
if ((str = parse_parentheses(str, &name_list, hint->base.hint_keyword))
== NULL)
return NULL;
hint->words = name_list;
/* We need both name and value to set GUC parameter. */
if (list_length(name_list) == 2)
{
hint->name = linitial(name_list);
hint->value = lsecond(name_list);
}
else
{
hint_ereport(hint->base.hint_str,
("%s hint requires name and value of GUC parameter.",
HINT_SET));
hint->base.state = HINT_STATE_ERROR;
}
return str;
}
static const char *
RowsHintParse(RowsHint *hint, HintState *hstate, Query *parse,
const char *str)
{
HintKeyword hint_keyword = hint->base.hint_keyword;
List *name_list = NIL;
char *rows_str;
char *end_ptr;
ListCell *l;
int i = 0;
if ((str = parse_parentheses(str, &name_list, hint_keyword)) == NULL)
return NULL;
/* Last element must be rows specification */
hint->nrels = list_length(name_list) - 1;
if (hint->nrels < 1)
{
hint_ereport(str,
("%s hint needs at least one relation followed by one correction term.",
hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
return str;
}
/*
* Transform relation names from list to array to sort them with qsort
* after.
*/
hint->relnames = palloc(sizeof(char *) * hint->nrels);
foreach (l, name_list)
{
if (hint->nrels <= i)
break;
hint->relnames[i] = lfirst(l);
i++;
}
/* Retieve rows estimation */
rows_str = list_nth(name_list, hint->nrels);
hint->rows_str = rows_str; /* store as-is for error logging */
if (rows_str[0] == '#')
{
hint->value_type = RVT_ABSOLUTE;
rows_str++;
}
else if (rows_str[0] == '+')
{
hint->value_type = RVT_ADD;
rows_str++;
}
else if (rows_str[0] == '-')
{
hint->value_type = RVT_SUB;
rows_str++;
}
else if (rows_str[0] == '*')
{
hint->value_type = RVT_MULTI;
rows_str++;
}
else
{
hint_ereport(rows_str, ("Unrecognized rows value type notation."));
hint->base.state = HINT_STATE_ERROR;
return str;
}
hint->rows = strtod(rows_str, &end_ptr);
if (*end_ptr)
{
hint_ereport(rows_str,
("%s hint requires valid number as rows estimation.",
hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
return str;
}
/* A join hint requires at least two relations */
if (hint->nrels < 2)
{
hint_ereport(str,
("%s hint requires at least two relations.",
hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
return str;
}
list_free(name_list);
/* Sort relnames in alphabetical order. */
qsort(hint->relnames, hint->nrels, sizeof(char *), RelnameCmp);
return str;
}
static const char *
ParallelHintParse(ParallelHint *hint, HintState *hstate, Query *parse,
const char *str)
{
HintKeyword hint_keyword = hint->base.hint_keyword;
List *name_list = NIL;
int length;
char *end_ptr;
int nworkers;
bool force_parallel = false;
if ((str = parse_parentheses(str, &name_list, hint_keyword)) == NULL)
return NULL;
/* Parse relation name and index name(s) if given hint accepts. */
length = list_length(name_list);
if (length < 2 || length > 3)
{
hint_ereport(")",
("wrong number of arguments (%d): %s",
length, hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
return str;
}
hint->relname = linitial(name_list);
/* The second parameter is number of workers */
hint->nworkers_str = list_nth(name_list, 1);
nworkers = strtod(hint->nworkers_str, &end_ptr);
if (*end_ptr || nworkers < 0 || nworkers > max_worker_processes)
{
if (*end_ptr)
hint_ereport(hint->nworkers_str,
("number of workers must be a number: %s",
hint->base.keyword));
else if (nworkers < 0)
hint_ereport(hint->nworkers_str,
("number of workers must be positive: %s",
hint->base.keyword));
else if (nworkers > max_worker_processes)
hint_ereport(hint->nworkers_str,
("number of workers = %d is larger than max_worker_processes(%d): %s",
nworkers, max_worker_processes, hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
}
hint->nworkers = nworkers;
/* optional third parameter is specified */
if (length == 3)
{
const char *modeparam = (const char *)list_nth(name_list, 2);
if (pg_strcasecmp(modeparam, "hard") == 0)
force_parallel = true;
else if (pg_strcasecmp(modeparam, "soft") != 0)
{
hint_ereport(modeparam,
("enforcement must be soft or hard: %s",
hint->base.keyword));
hint->base.state = HINT_STATE_ERROR;
}
}
hint->force_parallel = force_parallel;
if (hint->base.state != HINT_STATE_ERROR &&
nworkers > max_hint_nworkers)
max_hint_nworkers = nworkers;
return str;
}
/*
* set GUC parameter functions
*/
static int
get_current_scan_mask()
{
int mask = 0;
if (enable_seqscan)
mask |= ENABLE_SEQSCAN;
if (enable_indexscan)
mask |= ENABLE_INDEXSCAN;
if (enable_bitmapscan)
mask |= ENABLE_BITMAPSCAN;
if (enable_tidscan)
mask |= ENABLE_TIDSCAN;
if (enable_indexonlyscan)
mask |= ENABLE_INDEXONLYSCAN;
return mask;
}
static int
get_current_join_mask()
{
int mask = 0;
if (enable_nestloop)
mask |= ENABLE_NESTLOOP;
if (enable_mergejoin)
mask |= ENABLE_MERGEJOIN;
if (enable_hashjoin)
mask |= ENABLE_HASHJOIN;
return mask;
}
/*
* Sets GUC parameters without throwing exception. Returns false if something
* wrong.
*/
static int
set_config_option_noerror(const char *name, const char *value,
GucContext context, GucSource source,
GucAction action, bool changeVal, int elevel)
{
int result = 0;
MemoryContext ccxt = CurrentMemoryContext;
PG_TRY();
{
result = set_config_option(name, value, context, source,
action, changeVal, 0, false);
}
PG_CATCH();
{
ErrorData *errdata;
/* Save error info */
MemoryContextSwitchTo(ccxt);
errdata = CopyErrorData();
FlushErrorState();
ereport(elevel,
(errcode(errdata->sqlerrcode),
errmsg("%s", errdata->message),
errdata->detail ? errdetail("%s", errdata->detail) : 0,
errdata->hint ? errhint("%s", errdata->hint) : 0));
msgqno = qno;
FreeErrorData(errdata);
}
PG_END_TRY();
return result;
}
/*
* Sets GUC parameter of int32 type without throwing exceptions. Returns false
* if something wrong.
*/
static int
set_config_int32_option(const char *name, int32 value, GucContext context)
{
char buf[16]; /* enough for int32 */
if (snprintf(buf, 16, "%d", value) < 0)
{
ereport(pg_hint_plan_parse_message_level,
(errmsg ("Failed to convert integer to string: %d", value)));
return false;
}
return
set_config_option_noerror(name, buf, context,
PGC_S_SESSION, GUC_ACTION_SAVE, true,
pg_hint_plan_parse_message_level);
}
/*
* Sets GUC parameter of double type without throwing exceptions. Returns false
* if something wrong.
*/
static int
set_config_double_option(const char *name, double value, GucContext context)
{
char *buf = float8out_internal(value);
int result;
result = set_config_option_noerror(name, buf, context,
PGC_S_SESSION, GUC_ACTION_SAVE, true,
pg_hint_plan_parse_message_level);
pfree(buf);
return result;
}
/* setup scan method enforcement according to given options */
static void
setup_guc_enforcement(SetHint **options, int noptions, GucContext context)
{
int i;
for (i = 0; i < noptions; i++)
{
SetHint *hint = options[i];
int result;
if (!hint_state_enabled(hint))
continue;
result = set_config_option_noerror(hint->name, hint->value, context,
PGC_S_SESSION, GUC_ACTION_SAVE, true,
pg_hint_plan_parse_message_level);
if (result != 0)
hint->base.state = HINT_STATE_USED;
else
hint->base.state = HINT_STATE_ERROR;
}
return;
}
/*
* Setup parallel execution environment.
*
* If hint is not NULL, set up using it, elsewise reset to initial environment.
*/
static void
setup_parallel_plan_enforcement(ParallelHint *hint, HintState *state)
{
if (hint)
{
hint->base.state = HINT_STATE_USED;
set_config_int32_option("max_parallel_workers_per_gather",
hint->nworkers, state->context);
}
else
set_config_int32_option("max_parallel_workers_per_gather",
state->init_nworkers, state->context);
/* force means that enforce parallel as far as possible */
if (hint && hint->force_parallel && hint->nworkers > 0)
{
set_config_double_option("parallel_tuple_cost", 0.0, state->context);
set_config_double_option("parallel_setup_cost", 0.0, state->context);
set_config_int32_option("min_parallel_table_scan_size", 0,
state->context);
set_config_int32_option("min_parallel_index_scan_size", 0,
state->context);
}
else
{
set_config_double_option("parallel_tuple_cost",
state->init_paratup_cost, state->context);
set_config_double_option("parallel_setup_cost",
state->init_parasetup_cost, state->context);
set_config_int32_option("min_parallel_table_scan_size",
state->init_min_para_tablescan_size,
state->context);
set_config_int32_option("min_parallel_index_scan_size",
state->init_min_para_indexscan_size,
state->context);
}
}
#define SET_CONFIG_OPTION(name, type_bits) \
set_config_option_noerror((name), \
(mask & (type_bits)) ? "true" : "false", \
context, PGC_S_SESSION, GUC_ACTION_SAVE, true, ERROR)
/*
* Setup GUC environment to enforce scan methods. If scanhint is NULL, reset
* GUCs to the saved state in state.
*/
static void
setup_scan_method_enforcement(ScanMethodHint *scanhint, HintState *state)
{
unsigned char enforce_mask = state->init_scan_mask;
GucContext context = state->context;
unsigned char mask;
if (scanhint)
{
enforce_mask = scanhint->enforce_mask;
scanhint->base.state = HINT_STATE_USED;
}
if (enforce_mask == ENABLE_SEQSCAN || enforce_mask == ENABLE_INDEXSCAN ||
enforce_mask == ENABLE_BITMAPSCAN || enforce_mask == ENABLE_TIDSCAN
|| enforce_mask == (ENABLE_INDEXSCAN | ENABLE_INDEXONLYSCAN)
)
mask = enforce_mask;
else
mask = enforce_mask & current_hint_state->init_scan_mask;
SET_CONFIG_OPTION("enable_seqscan", ENABLE_SEQSCAN);
SET_CONFIG_OPTION("enable_indexscan", ENABLE_INDEXSCAN);
SET_CONFIG_OPTION("enable_bitmapscan", ENABLE_BITMAPSCAN);
SET_CONFIG_OPTION("enable_tidscan", ENABLE_TIDSCAN);
SET_CONFIG_OPTION("enable_indexonlyscan", ENABLE_INDEXONLYSCAN);
}
static void
set_join_config_options(unsigned char enforce_mask, GucContext context)
{
unsigned char mask;
if (enforce_mask == ENABLE_NESTLOOP || enforce_mask == ENABLE_MERGEJOIN ||
enforce_mask == ENABLE_HASHJOIN)
mask = enforce_mask;
else
mask = enforce_mask & current_hint_state->init_join_mask;
SET_CONFIG_OPTION("enable_nestloop", ENABLE_NESTLOOP);
SET_CONFIG_OPTION("enable_mergejoin", ENABLE_MERGEJOIN);
SET_CONFIG_OPTION("enable_hashjoin", ENABLE_HASHJOIN);
/*
* Hash join may be rejected for the reason of estimated memory usage. Try
* getting rid of that limitation. This change on work_mem is reverted just
* after searching join path so no suginificant side-effects are expected.
*/
if (enforce_mask == ENABLE_HASHJOIN)
{
char buf[32];
/* See final_cost_hashjoin(). */
if (work_mem < MAX_KILOBYTES)
{
snprintf(buf, sizeof(buf), UINT64_FORMAT, (uint64)MAX_KILOBYTES);
set_config_option_noerror("work_mem", buf,
context, PGC_S_SESSION, GUC_ACTION_SAVE,
true, ERROR);
}
}
}
/*
* Push a hint into hint stack which is implemented with List struct. Head of
* list is top of stack.
*/
static void
push_hint(HintState *hstate)
{
/* Prepend new hint to the list means pushing to stack. */
HintStateStack = lcons(hstate, HintStateStack);
/* Pushed hint is the one which should be used hereafter. */
current_hint_state = hstate;
}
/* Pop a hint from hint stack. Popped hint is automatically discarded. */
static void
pop_hint(void)
{
/* Hint stack must not be empty. */
if(HintStateStack == NIL)
elog(ERROR, "hint stack is empty");
/*
* Take a hint at the head from the list, and free it. Switch
* current_hint_state to point new head (NULL if the list is empty).
*/
HintStateStack = list_delete_first(HintStateStack);
HintStateDelete(current_hint_state);
if(HintStateStack == NIL)
current_hint_state = NULL;
else
current_hint_state = (HintState *) lfirst(list_head(HintStateStack));
}
/*
* Retrieve and store hint string from given query or from the hint table.
*/
static void
get_current_hint_string(ParseState *pstate, Query *query)
{
const char *query_str;
MemoryContext oldcontext;
/* do nothing under hint table search */
if (hint_inhibit_level > 0)
return;
/* We alredy have one, don't parse it again. */
if (current_hint_retrieved)
return;
/* Not support utility mode yet */
if (query->utilityStmt)
return;
/* Don't parse the current query hereafter */
current_hint_retrieved = true;
if (!pg_hint_plan_enable_hint)
{
if (current_hint_str)
{
pfree((void *)current_hint_str);
current_hint_str = NULL;
}
return;
}
/* increment the query number */
qnostr[0] = 0;
if (debug_level > 1)
snprintf(qnostr, sizeof(qnostr), "[qno=0x%x]", qno++);
qno++;
/* search the hint table for a hint if requested */
if (pg_hint_plan_enable_hint_table)
{
int query_len;
JumbleState *jstate = NULL;
Query *jumblequery;
char *normalized_query = NULL;
query_str = get_query_string(pstate, query, &jumblequery);
/* If this query is not for hint, just return */
if (!query_str)
return;
/* clear the previous hint string */
if (current_hint_str)
{
pfree((void *)current_hint_str);
current_hint_str = NULL;
}
if (jumblequery)
{
jstate = JumbleQueryDirect(query, query_str);
/*
* Normalize the query string by replacing constants with '?'
*/
/*
* Search hint string which is stored keyed by query string
* and application name. The query string is normalized to allow
* fuzzy matching.
*
* Adding 1 byte to query_len ensures that the returned string has
* a terminating NULL.
*/
query_len = strlen(query_str) + 1;
normalized_query =
generate_normalized_query(jstate, query_str, 0, &query_len,
GetDatabaseEncoding());
/*
* find a hint for the normalized query. the result should be in
* TopMemoryContext
*/
oldcontext = MemoryContextSwitchTo(TopMemoryContext);
current_hint_str =
get_hints_from_table(normalized_query, application_name);
MemoryContextSwitchTo(oldcontext);
if (debug_level > 1)
{
if (current_hint_str)
ereport(pg_hint_plan_debug_message_level,
(errmsg("pg_hint_plan[qno=0x%x]: "
"post_parse_analyze_hook: "
"hints from table: \"%s\": "
"normalized_query=\"%s\", "
"application name =\"%s\"",
qno, current_hint_str,
normalized_query, application_name),
errhidestmt(msgqno != qno),
errhidecontext(msgqno != qno)));
else
ereport(pg_hint_plan_debug_message_level,
(errmsg("pg_hint_plan[qno=0x%x]: "
"no match found in table: "
"application name = \"%s\", "
"normalized_query=\"%s\"",
qno, application_name,
normalized_query),
errhidestmt(msgqno != qno),
errhidecontext(msgqno != qno)));
msgqno = qno;
}
}
/* return if we have hint here */
if (current_hint_str)
return;
}
else
query_str = get_query_string(pstate, query, NULL);
if (query_str)
{
/*
* get hints from the comment. However we may have the same query
* string with the previous call, but the extra comparison seems no
* use..
*/
if (current_hint_str)
{
pfree((void *)current_hint_str);
current_hint_str = NULL;
}
oldcontext = MemoryContextSwitchTo(TopMemoryContext);
current_hint_str = get_hints_from_comment(query_str);
MemoryContextSwitchTo(oldcontext);
}
else
{
/*
* Failed to get query. We would be in fetching invalidated
* plancache. Try the next chance.
*/
current_hint_retrieved = false;
}
if (debug_level > 1)
{
if (debug_level == 1 && query_str && debug_query_string &&
strcmp(query_str, debug_query_string))
ereport(pg_hint_plan_debug_message_level,
(errmsg("hints in comment=\"%s\"",
current_hint_str ? current_hint_str : "(none)"),
errhidestmt(msgqno != qno),
errhidecontext(msgqno != qno)));
else
ereport(pg_hint_plan_debug_message_level,
(errmsg("hints in comment=\"%s\", query=\"%s\", debug_query_string=\"%s\"",
current_hint_str ? current_hint_str : "(none)",
query_str ? query_str : "(none)",
debug_query_string ? debug_query_string : "(none)"),
errhidestmt(msgqno != qno),
errhidecontext(msgqno != qno)));
msgqno = qno;
}
}
/*
* Retrieve hint string from the current query.
*/
static void
pg_hint_plan_post_parse_analyze(ParseState *pstate,
Query *query,
JumbleState *jstate)
{
if (prev_post_parse_analyze_hook)
prev_post_parse_analyze_hook(pstate, query, jstate);
/* always retrieve hint from the top-level query string */
if (plpgsql_recurse_level == 0)
current_hint_retrieved = false;
get_current_hint_string(pstate, query);
}
/*
* We need to reset current_hint_retrieved flag always when a command execution
* is finished. This is true even for a pure utility command that doesn't
* involve planning phase.
*/
static void
pg_hint_plan_ProcessUtility(PlannedStmt *pstmt, const char *queryString,
bool readOnlyTree, ProcessUtilityContext context,
ParamListInfo params, QueryEnvironment *queryEnv,
DestReceiver *dest, QueryCompletion *qc)
{
if (prev_ProcessUtility_hook)
prev_ProcessUtility_hook(pstmt, queryString, readOnlyTree, context, params, queryEnv,
dest, qc);
else
standard_ProcessUtility(pstmt, queryString, readOnlyTree, context, params, queryEnv,
dest, qc);
if (plpgsql_recurse_level == 0)
current_hint_retrieved = false;
}
/*
* Read and set up hint information
*/
static PlannedStmt *
pg_hint_plan_planner(Query *parse, const char *query_string,
int cursorOptions, ParamListInfo boundParams)
{
int save_nestlevel;
PlannedStmt *result;
const char *prev_hint_str = NULL;
/*
* Use standard planner if pg_hint_plan is disabled or current nesting
* depth is nesting depth of SPI calls. Other hook functions try to change
* plan with current_hint_state if any, so set it to NULL.
*/
if (!pg_hint_plan_enable_hint || hint_inhibit_level > 0)
{
if (debug_level > 1)
ereport(pg_hint_plan_debug_message_level,
(errmsg ("pg_hint_plan%s: planner: enable_hint=%d,"
" hint_inhibit_level=%d",
qnostr, pg_hint_plan_enable_hint,
hint_inhibit_level),
errhidestmt(msgqno != qno)));
msgqno = qno;
goto standard_planner_proc;
}
/*
* Support for nested plpgsql functions. This is quite ugly but this is the
* only point I could find where I can get the query string.
*/
if (plpgsql_recurse_level > 0 &&
error_context_stack && error_context_stack->arg)
{
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(TopMemoryContext);
current_hint_str =
get_hints_from_comment((char *)error_context_stack->arg);
MemoryContextSwitchTo(oldcontext);
}
/*
* Query execution in extended protocol can be started without the analyze
* phase. In the case retrieve hint string here.
*/
if (!current_hint_str)
get_current_hint_string(NULL, parse);
/* No hint, go the normal way */
if (!current_hint_str)
goto standard_planner_proc;
/* parse the hint into hint state struct */
hstate = create_hintstate(parse, pstrdup(current_hint_str));
/* run standard planner if the statement has not valid hint */
if (!hstate)
goto standard_planner_proc;
/*
* Push new hint struct to the hint stack to disable previous hint context.
* There should be no ERROR-level failures until we begin the
* PG_TRY/PG_CATCH block below to ensure a consistent stack handling all
* the time.
*/
push_hint(hstate);
/* Set scan enforcement here. */
save_nestlevel = NewGUCNestLevel();
/*
* The planner call below may replace current_hint_str. Store and restore
* it so that the subsequent planning in the upper level doesn't get
* confused.
*/
recurse_level++;
prev_hint_str = current_hint_str;
current_hint_str = NULL;
/*
* Use PG_TRY mechanism to recover GUC parameters and current_hint_state to
* the state when this planner started when error occurred in planner. We
* do this here to minimize the window where the hints currently pushed on
* the stack could not be popped out of it.
*/
PG_TRY();
{
/* Apply Set hints, then save it as the initial state */
setup_guc_enforcement(current_hint_state->set_hints,
current_hint_state->num_hints[HINT_TYPE_SET],
current_hint_state->context);
current_hint_state->init_scan_mask = get_current_scan_mask();
current_hint_state->init_join_mask = get_current_join_mask();
current_hint_state->init_min_para_tablescan_size =
min_parallel_table_scan_size;
current_hint_state->init_min_para_indexscan_size =
min_parallel_index_scan_size;
current_hint_state->init_paratup_cost = parallel_tuple_cost;
current_hint_state->init_parasetup_cost = parallel_setup_cost;
/*
* max_parallel_workers_per_gather should be non-zero here if Workers
* hint is specified.
*/
if (max_hint_nworkers > 0 && max_parallel_workers_per_gather < 1)
set_config_int32_option("max_parallel_workers_per_gather",
1, current_hint_state->context);
current_hint_state->init_nworkers = max_parallel_workers_per_gather;
if (debug_level > 1)
{
ereport(pg_hint_plan_debug_message_level,
(errhidestmt(msgqno != qno),
errmsg("pg_hint_plan%s: planner", qnostr)));
msgqno = qno;
}
if (prev_planner)
result = (*prev_planner) (parse, query_string, cursorOptions, boundParams);
else
result = standard_planner(parse, query_string, cursorOptions, boundParams);
current_hint_str = prev_hint_str;
recurse_level--;
}
PG_CATCH();
{
/*
* Rollback changes of GUC parameters, and pop current hint context
* from hint stack to rewind the state.
*/
current_hint_str = prev_hint_str;
recurse_level--;
AtEOXact_GUC(true, save_nestlevel);
pop_hint();
PG_RE_THROW();
}
PG_END_TRY();
/*
* current_hint_str is useless after planning of the top-level query.
*/
if (recurse_level < 1 && current_hint_str)
{
pfree((void *)current_hint_str);
current_hint_str = NULL;
current_hint_retrieved = false;
}
/* Print hint logs if Planner is used */
if (result->planGen == PLANGEN_PLANNER)
{
/* Print hint in debug mode. */
if (debug_level == 1)
HintStateDump(current_hint_state);
else if (debug_level > 1)
HintStateDump2(current_hint_state);
}
/*
* Rollback changes of GUC parameters, and pop current hint context from
* hint stack to rewind the state.
*/
AtEOXact_GUC(true, save_nestlevel);
pop_hint();
return result;
standard_planner_proc:
if (debug_level > 1)
{
ereport(pg_hint_plan_debug_message_level,
(errhidestmt(msgqno != qno),
errmsg("pg_hint_plan%s: planner: no valid hint",
qnostr)));
msgqno = qno;
}
current_hint_state = NULL;
if (prev_planner)
result = (*prev_planner) (parse, query_string, cursorOptions, boundParams);
else
result = standard_planner(parse, query_string, cursorOptions, boundParams);
/* The upper-level planner still needs the current hint state */
if (HintStateStack != NIL)
current_hint_state = (HintState *) lfirst(list_head(HintStateStack));
return result;
}
/*
* Find scan method hint to be applied to the given relation
*
*/
static ScanMethodHint *
find_scan_hint(PlannerInfo *root, Index relid)
{
RelOptInfo *rel;
RangeTblEntry *rte;
ScanMethodHint *real_name_hint = NULL;
ScanMethodHint *alias_hint = NULL;
int i;
/* This should not be a join rel */
Assert(relid > 0);
rel = root->simple_rel_array[relid];
/*
* This function is called for any RelOptInfo or its inheritance parent if
* any. If we are called from inheritance planner, the RelOptInfo for the
* parent of target child relation is not set in the planner info.
*
* Otherwise we should check that the reloptinfo is base relation or
* inheritance children.
*/
if (rel &&
rel->reloptkind != RELOPT_BASEREL &&
rel->reloptkind != RELOPT_OTHER_MEMBER_REL)
return NULL;
/*
* This is baserel or appendrel children. We can refer to RangeTblEntry.
*/
rte = root->simple_rte_array[relid];
Assert(rte);
/* We don't hint on other than relation and foreign tables */
if (rte->rtekind != RTE_RELATION ||
rte->relkind == RELKIND_FOREIGN_TABLE)
return NULL;
/* Find scan method hint, which matches given names, from the list. */
for (i = 0; i < current_hint_state->num_hints[HINT_TYPE_SCAN_METHOD]; i++)
{
ScanMethodHint *hint = current_hint_state->scan_hints[i];
/* We ignore disabled hints. */
if (!hint_state_enabled(hint))
continue;
if (!alias_hint &&
RelnameCmp(&rte->eref->aliasname, &hint->relname) == 0)
alias_hint = hint;
/* check the real name for appendrel children */
if (!real_name_hint &&
rel && rel->reloptkind == RELOPT_OTHER_MEMBER_REL)
{
char *realname = get_rel_name(rte->relid);
if (realname && RelnameCmp(&realname, &hint->relname) == 0)
real_name_hint = hint;
}
/* No more match expected, break */
if(alias_hint && real_name_hint)
break;
}
/* real name match precedes alias match */
if (real_name_hint)
return real_name_hint;
return alias_hint;
}
static ParallelHint *
find_parallel_hint(PlannerInfo *root, Index relid)
{
RelOptInfo *rel;
RangeTblEntry *rte;
ParallelHint *real_name_hint = NULL;
ParallelHint *alias_hint = NULL;
int i;
/* This should not be a join rel */
Assert(relid > 0);
rel = root->simple_rel_array[relid];
/*
* Parallel planning is appliable only on base relation, which has
* RelOptInfo.
*/
if (!rel)
return NULL;
/*
* We have set root->glob->parallelModeOK if needed. What we should do here
* is just following the decision of planner.
*/
if (!rel->consider_parallel)
return NULL;
/*
* This is baserel or appendrel children. We can refer to RangeTblEntry.
*/
rte = root->simple_rte_array[relid];
Assert(rte);
/* Find parallel method hint, which matches given names, from the list. */
for (i = 0; i < current_hint_state->num_hints[HINT_TYPE_PARALLEL]; i++)
{
ParallelHint *hint = current_hint_state->parallel_hints[i];
/* We ignore disabled hints. */
if (!hint_state_enabled(hint))
continue;
if (!alias_hint &&
RelnameCmp(&rte->eref->aliasname, &hint->relname) == 0)
alias_hint = hint;
/* check the real name for appendrel children */
if (!real_name_hint &&
rel && rel->reloptkind == RELOPT_OTHER_MEMBER_REL)
{
char *realname = get_rel_name(rte->relid);
if (realname && RelnameCmp(&realname, &hint->relname) == 0)
real_name_hint = hint;
}
/* No more match expected, break */
if(alias_hint && real_name_hint)
break;
}
/* real name match precedes alias match */
if (real_name_hint)
return real_name_hint;
return alias_hint;
}
/*
* regexeq
*
* Returns TRUE on match, FALSE on no match.
*
* s1 --- the data to match against
* s2 --- the pattern
*
* Because we copy s1 to NameData, make the size of s1 less than NAMEDATALEN.
*/
static bool
regexpeq(const char *s1, const char *s2)
{
NameData name;
text *regexp;
Datum result;
strcpy(name.data, s1);
regexp = cstring_to_text(s2);
result = DirectFunctionCall2Coll(nameregexeq,
DEFAULT_COLLATION_OID,
NameGetDatum(&name),
PointerGetDatum(regexp));
return DatumGetBool(result);
}
/* Remove indexes instructed not to use by hint. */
static void
restrict_indexes(PlannerInfo *root, ScanMethodHint *hint, RelOptInfo *rel,
bool using_parent_hint)
{
ListCell *cell;
StringInfoData buf;
RangeTblEntry *rte = root->simple_rte_array[rel->relid];
Oid relationObjectId = rte->relid;
/*
* We delete all the IndexOptInfo list and prevent you from being usable by
* a scan.
*/
if (hint->enforce_mask == ENABLE_SEQSCAN ||
hint->enforce_mask == ENABLE_TIDSCAN)
{
list_free_deep(rel->indexlist);
rel->indexlist = NIL;
hint->base.state = HINT_STATE_USED;
return;
}
/*
* When a list of indexes is not specified, we just use all indexes.
*/
if (hint->indexnames == NIL)
return;
/*
* Leaving only an specified index, we delete it from a IndexOptInfo list
* other than it.
*/
if (debug_level > 0)
initStringInfo(&buf);
foreach (cell, rel->indexlist)
{
IndexOptInfo *info = (IndexOptInfo *) lfirst(cell);
char *indexname = get_rel_name(info->indexoid);
ListCell *l;
bool use_index = false;
foreach(l, hint->indexnames)
{
char *hintname = (char *) lfirst(l);
bool result;
if (hint->regexp)
result = regexpeq(indexname, hintname);
else
result = RelnameCmp(&indexname, &hintname) == 0;
if (result)
{
use_index = true;
if (debug_level > 0)
{
appendStringInfoCharMacro(&buf, ' ');
quote_value(&buf, indexname);
}
break;
}
}
/*
* Apply index restriction of parent hint to children. Since index
* inheritance is not explicitly described we should search for an
* children's index with the same definition to that of the parent.
*/
if (using_parent_hint && !use_index)
{
foreach(l, current_hint_state->parent_index_infos)
{
int i;
HeapTuple ht_idx;
ParentIndexInfo *p_info = (ParentIndexInfo *)lfirst(l);
/*
* we check the 'same' index by comparing uniqueness, access
* method and index key columns.
*/
if (p_info->indisunique != info->unique ||
p_info->method != info->relam ||
list_length(p_info->column_names) != info->ncolumns)
continue;
/* Check if index key columns match */
for (i = 0; i < info->ncolumns; i++)
{
char *c_attname = NULL;
char *p_attname = NULL;
p_attname = list_nth(p_info->column_names, i);
/*
* if both of the key of the same position are expressions,
* ignore them for now and check later.
*/
if (info->indexkeys[i] == 0 && !p_attname)
continue;
/* deny if one is expression while another is not */
if (info->indexkeys[i] == 0 || !p_attname)
break;
c_attname = get_attname(relationObjectId,
info->indexkeys[i], false);
/* deny if any of column attributes don't match */
if (strcmp(p_attname, c_attname) != 0 ||
p_info->indcollation[i] != info->indexcollations[i] ||
p_info->opclass[i] != info->opcintype[i])
break;
/*
* Compare index ordering if this index is ordered.
*
* We already confirmed that this and the parent indexes
* share the same column set (actually only the length of
* the column set is compard, though.) and index access
* method. So if this index is unordered, the parent can be
* assumed to be be unodered. Thus no need to bother
* checking the parent's orderedness.
*/
if (info->sortopfamily != NULL &&
(((p_info->indoption[i] & INDOPTION_DESC) != 0)
!= info->reverse_sort[i] ||
((p_info->indoption[i] & INDOPTION_NULLS_FIRST) != 0)
!= info->nulls_first[i]))
break;
}
/* deny this if any difference found */
if (i != info->ncolumns)
continue;
/* check on key expressions */
if ((p_info->expression_str && (info->indexprs != NIL)) ||
(p_info->indpred_str && (info->indpred != NIL)))
{
/* fetch the index of this child */
ht_idx = SearchSysCache1(INDEXRELID,
ObjectIdGetDatum(info->indexoid));
/* check expressions if both expressions are available */
if (p_info->expression_str &&
!heap_attisnull(ht_idx, Anum_pg_index_indexprs, NULL))
{
Datum exprsDatum;
bool isnull;
Datum result;
/*
* to change the expression's parameter of child's
* index to strings
*/
exprsDatum = SysCacheGetAttr(INDEXRELID, ht_idx,
Anum_pg_index_indexprs,
&isnull);
result = DirectFunctionCall2(pg_get_expr,
exprsDatum,
ObjectIdGetDatum(
relationObjectId));
/* deny if expressions don't match */
if (strcmp(p_info->expression_str,
text_to_cstring(DatumGetTextP(result))) != 0)
{
/* Clean up */
ReleaseSysCache(ht_idx);
continue;
}
}
/* compare index predicates */
if (p_info->indpred_str &&
!heap_attisnull(ht_idx, Anum_pg_index_indpred, NULL))
{
Datum predDatum;
bool isnull;
Datum result;
predDatum = SysCacheGetAttr(INDEXRELID, ht_idx,
Anum_pg_index_indpred,
&isnull);
result = DirectFunctionCall2(pg_get_expr,
predDatum,
ObjectIdGetDatum(
relationObjectId));
if (strcmp(p_info->indpred_str,
text_to_cstring(DatumGetTextP(result))) != 0)
{
/* Clean up */
ReleaseSysCache(ht_idx);
continue;
}
}
/* Clean up */
ReleaseSysCache(ht_idx);
}
else if (p_info->expression_str || (info->indexprs != NIL))
continue;
else if (p_info->indpred_str || (info->indpred != NIL))
continue;
use_index = true;
/* to log the candidate of index */
if (debug_level > 0)
{
appendStringInfoCharMacro(&buf, ' ');
quote_value(&buf, indexname);
}
break;
}
}
if (!use_index)
rel->indexlist = foreach_delete_current(rel->indexlist, cell);
pfree(indexname);
}
if (debug_level == 1)
{
StringInfoData rel_buf;
char *disprelname = "";
/*
* If this hint targetted the parent, use the real name of this
* child. Otherwise use hint specification.
*/
if (using_parent_hint)
disprelname = get_rel_name(rte->relid);
else
disprelname = hint->relname;
initStringInfo(&rel_buf);
quote_value(&rel_buf, disprelname);
ereport(pg_hint_plan_debug_message_level,
(errmsg("available indexes for %s(%s):%s",
hint->base.keyword,
rel_buf.data,
buf.data)));
pfree(buf.data);
pfree(rel_buf.data);
}
}
/*
* Return information of index definition.
*/
static ParentIndexInfo *
get_parent_index_info(Oid indexoid, Oid relid)
{
ParentIndexInfo *p_info = palloc(sizeof(ParentIndexInfo));
Relation indexRelation;
Form_pg_index index;
char *attname;
int i;
indexRelation = index_open(indexoid, RowExclusiveLock);
index = indexRelation->rd_index;
p_info->indisunique = index->indisunique;
p_info->method = indexRelation->rd_rel->relam;
p_info->column_names = NIL;
p_info->indcollation = (Oid *) palloc(sizeof(Oid) * index->indnatts);
p_info->opclass = (Oid *) palloc(sizeof(Oid) * index->indnatts);
p_info->indoption = (int16 *) palloc(sizeof(Oid) * index->indnatts);
/*
* Collect relation attribute names of index columns for index
* identification, not index attribute names. NULL means expression index
* columns.
*/
for (i = 0; i < index->indnatts; i++)
{
attname = get_attname(relid, index->indkey.values[i], true);
p_info->column_names = lappend(p_info->column_names, attname);
p_info->indcollation[i] = indexRelation->rd_indcollation[i];
p_info->opclass[i] = indexRelation->rd_opcintype[i];
p_info->indoption[i] = indexRelation->rd_indoption[i];
}
/*
* to check to match the expression's parameter of index with child indexes
*/
p_info->expression_str = NULL;
if(!heap_attisnull(indexRelation->rd_indextuple, Anum_pg_index_indexprs,
NULL))
{
Datum exprsDatum;
bool isnull;
Datum result;
exprsDatum = SysCacheGetAttr(INDEXRELID, indexRelation->rd_indextuple,
Anum_pg_index_indexprs, &isnull);
result = DirectFunctionCall2(pg_get_expr,
exprsDatum,
ObjectIdGetDatum(relid));
p_info->expression_str = text_to_cstring(DatumGetTextP(result));
}
/*
* to check to match the predicate's parameter of index with child indexes
*/
p_info->indpred_str = NULL;
if(!heap_attisnull(indexRelation->rd_indextuple, Anum_pg_index_indpred,
NULL))
{
Datum predDatum;
bool isnull;
Datum result;
predDatum = SysCacheGetAttr(INDEXRELID, indexRelation->rd_indextuple,
Anum_pg_index_indpred, &isnull);
result = DirectFunctionCall2(pg_get_expr,
predDatum,
ObjectIdGetDatum(relid));
p_info->indpred_str = text_to_cstring(DatumGetTextP(result));
}
index_close(indexRelation, NoLock);
return p_info;
}
/*
* cancel hint enforcement
*/
static void
reset_hint_enforcement()
{
setup_scan_method_enforcement(NULL, current_hint_state);
setup_parallel_plan_enforcement(NULL, current_hint_state);
}
/*
* Set planner guc parameters according to corresponding scan hints. Returns
* bitmap of HintTypeBitmap. If shint or phint is not NULL, set used hint
* there respectively.
*/
static int
setup_hint_enforcement(PlannerInfo *root, RelOptInfo *rel,
ScanMethodHint **rshint, ParallelHint **rphint)
{
Index new_parent_relid = 0;
ListCell *l;
ScanMethodHint *shint = NULL;
ParallelHint *phint = NULL;
bool inhparent = root->simple_rte_array[rel->relid]->inh;
Oid relationObjectId = root->simple_rte_array[rel->relid]->relid;
int ret = 0;
/* reset returns if requested */
if (rshint != NULL) *rshint = NULL;
if (rphint != NULL) *rphint = NULL;
/*
* We could register the parent relation of the following children here
* when inhparent == true but inheritnce planner doesn't call this function
* for parents. Since we cannot distinguish who called this function we
* cannot do other than always seeking the parent regardless of who called
* this function.
*/
if (inhparent)
{
/* set up only parallel hints for parent relation */
phint = find_parallel_hint(root, rel->relid);
if (phint)
{
setup_parallel_plan_enforcement(phint, current_hint_state);
if (rphint) *rphint = phint;
ret |= HINT_BM_PARALLEL;
return ret;
}
if (debug_level > 1)
ereport(pg_hint_plan_debug_message_level,
(errhidestmt(true),
errmsg ("pg_hint_plan%s: setup_hint_enforcement"
" skipping inh parent: relation=%u(%s), inhparent=%d,"
" current_hint_state=%p, hint_inhibit_level=%d",
qnostr, relationObjectId,
get_rel_name(relationObjectId),
inhparent, current_hint_state, hint_inhibit_level)));
return 0;
}
if (bms_num_members(rel->top_parent_relids) == 1)
{
new_parent_relid = bms_next_member(rel->top_parent_relids, -1);
current_hint_state->current_root = root;
Assert(new_parent_relid > 0);
}
else
{
/* This relation doesn't have a parent. Cancel current_hint_state. */
current_hint_state->parent_relid = 0;
current_hint_state->parent_scan_hint = NULL;
current_hint_state->parent_parallel_hint = NULL;
}
if (new_parent_relid > 0)
{
/*
* Here we found a new parent for the current relation. Scan continues
* hint to other childrens of this parent so remember it to avoid
* redundant setup cost.
*/
current_hint_state->parent_relid = new_parent_relid;
/* Find hints for the parent */
current_hint_state->parent_scan_hint =
find_scan_hint(root, current_hint_state->parent_relid);
current_hint_state->parent_parallel_hint =
find_parallel_hint(root, current_hint_state->parent_relid);
/*
* If hint is found for the parent, apply it for this child instead
* of its own.
*/
if (current_hint_state->parent_scan_hint)
{
ScanMethodHint * pshint = current_hint_state->parent_scan_hint;
pshint->base.state = HINT_STATE_USED;
/* Apply index mask in the same manner to the parent. */
if (pshint->indexnames)
{
Oid parentrel_oid;
Relation parent_rel;
parentrel_oid =
root->simple_rte_array[current_hint_state->parent_relid]->relid;
parent_rel = heap_open(parentrel_oid, NoLock);
/* Search the parent relation for indexes match the hint spec */
foreach(l, RelationGetIndexList(parent_rel))
{
Oid indexoid = lfirst_oid(l);
char *indexname = get_rel_name(indexoid);
ListCell *lc;
ParentIndexInfo *parent_index_info;
foreach(lc, pshint->indexnames)
{
if (RelnameCmp(&indexname, &lfirst(lc)) == 0)
break;
}
if (!lc)
continue;
parent_index_info =
get_parent_index_info(indexoid, parentrel_oid);
current_hint_state->parent_index_infos =
lappend(current_hint_state->parent_index_infos,
parent_index_info);
}
heap_close(parent_rel, NoLock);
}
}
}
shint = find_scan_hint(root, rel->relid);
if (!shint)
shint = current_hint_state->parent_scan_hint;
if (shint)
{
bool using_parent_hint =
(shint == current_hint_state->parent_scan_hint);
ret |= HINT_BM_SCAN_METHOD;
/* Setup scan enforcement environment */
setup_scan_method_enforcement(shint, current_hint_state);
/* restrict unwanted inexes */
restrict_indexes(root, shint, rel, using_parent_hint);
if (debug_level > 1)
{
char *additional_message = "";
if (shint == current_hint_state->parent_scan_hint)
additional_message = " by parent hint";
ereport(pg_hint_plan_debug_message_level,
(errhidestmt(true),
errmsg ("pg_hint_plan%s: setup_hint_enforcement"
" index deletion%s:"
" relation=%u(%s), inhparent=%d, "
"current_hint_state=%p,"
" hint_inhibit_level=%d, scanmask=0x%x",
qnostr, additional_message,
relationObjectId,
get_rel_name(relationObjectId),
inhparent, current_hint_state,
hint_inhibit_level,
shint->enforce_mask)));
}
}
/* Do the same for parallel plan enforcement */
phint = find_parallel_hint(root, rel->relid);
if (!phint)
phint = current_hint_state->parent_parallel_hint;
setup_parallel_plan_enforcement(phint, current_hint_state);
if (phint)
ret |= HINT_BM_PARALLEL;
/* Nothing to apply. Reset the scan mask to intial state */
if (!shint && ! phint)
{
if (debug_level > 1)
ereport(pg_hint_plan_debug_message_level,
(errhidestmt (true),
errmsg ("pg_hint_plan%s: setup_hint_enforcement"
" no hint applied:"
" relation=%u(%s), inhparent=%d, current_hint=%p,"
" hint_inhibit_level=%d, scanmask=0x%x",
qnostr, relationObjectId,
get_rel_name(relationObjectId),
inhparent, current_hint_state, hint_inhibit_level,
current_hint_state->init_scan_mask)));
setup_scan_method_enforcement(NULL, current_hint_state);
return ret;
}
if (rshint != NULL) *rshint = shint;
if (rphint != NULL) *rphint = phint;
return ret;
}
/*
* Return index of relation which matches given aliasname, or 0 if not found.
* If same aliasname was used multiple times in a query, return -1.
*/
static int
find_relid_aliasname(PlannerInfo *root, char *aliasname, List *initial_rels,
const char *str)
{
int i;
Index found = 0;
for (i = 1; i < root->simple_rel_array_size; i++)
{
ListCell *l;
if (root->simple_rel_array[i] == NULL)
continue;
Assert(i == root->simple_rel_array[i]->relid);
if (RelnameCmp(&aliasname,
&root->simple_rte_array[i]->eref->aliasname) != 0)
continue;
foreach(l, initial_rels)
{
RelOptInfo *rel = (RelOptInfo *) lfirst(l);
if (rel->reloptkind == RELOPT_BASEREL)
{
if (rel->relid != i)
continue;
}
else
{
Assert(rel->reloptkind == RELOPT_JOINREL);
if (!bms_is_member(i, rel->relids))
continue;
}
if (found != 0)
{
hint_ereport(str,
("Relation name \"%s\" is ambiguous.",
aliasname));
return -1;
}
found = i;
break;
}
}
return found;
}
/*
* Return join hint which matches given joinrelids.
*/
static JoinMethodHint *
find_join_hint(Relids joinrelids)
{
List *join_hint;
ListCell *l;
join_hint = current_hint_state->join_hint_level[bms_num_members(joinrelids)];
foreach(l, join_hint)
{
JoinMethodHint *hint = (JoinMethodHint *) lfirst(l);
if (bms_equal(joinrelids, hint->joinrelids))
return hint;
}
return NULL;
}
static Relids
OuterInnerJoinCreate(OuterInnerRels *outer_inner, LeadingHint *leading_hint,
PlannerInfo *root, List *initial_rels, HintState *hstate, int nbaserel)
{
OuterInnerRels *outer_rels;
OuterInnerRels *inner_rels;
Relids outer_relids;
Relids inner_relids;
Relids join_relids;
JoinMethodHint *hint;
if (outer_inner->relation != NULL)
{
return bms_make_singleton(
find_relid_aliasname(root, outer_inner->relation,
initial_rels,
leading_hint->base.hint_str));
}
outer_rels = linitial(outer_inner->outer_inner_pair);
inner_rels = llast(outer_inner->outer_inner_pair);
outer_relids = OuterInnerJoinCreate(outer_rels,
leading_hint,
root,
initial_rels,
hstate,
nbaserel);
inner_relids = OuterInnerJoinCreate(inner_rels,
leading_hint,
root,
initial_rels,
hstate,
nbaserel);
join_relids = bms_add_members(outer_relids, inner_relids);
if (bms_num_members(join_relids) > nbaserel)
return join_relids;
/*
* If we don't have join method hint, create new one for the
* join combination with all join methods are enabled.
*/
hint = find_join_hint(join_relids);
if (hint == NULL)
{
/*
* Here relnames is not set, since Relids bitmap is sufficient to
* control paths of this query afterward.
*/
hint = (JoinMethodHint *) JoinMethodHintCreate(
leading_hint->base.hint_str,
HINT_LEADING,
HINT_KEYWORD_LEADING);
hint->base.state = HINT_STATE_USED;
hint->nrels = bms_num_members(join_relids);
hint->enforce_mask = ENABLE_ALL_JOIN;
hint->joinrelids = bms_copy(join_relids);
hint->inner_nrels = bms_num_members(inner_relids);
hint->inner_joinrelids = bms_copy(inner_relids);
hstate->join_hint_level[hint->nrels] =
lappend(hstate->join_hint_level[hint->nrels], hint);
}
else
{
hint->inner_nrels = bms_num_members(inner_relids);
hint->inner_joinrelids = bms_copy(inner_relids);
}
return join_relids;
}
static Relids
create_bms_of_relids(Hint *base, PlannerInfo *root, List *initial_rels,
int nrels, char **relnames)
{
int relid;
Relids relids = NULL;
int j;
char *relname;
for (j = 0; j < nrels; j++)
{
relname = relnames[j];
relid = find_relid_aliasname(root, relname, initial_rels,
base->hint_str);
if (relid == -1)
base->state = HINT_STATE_ERROR;
/*
* the aliasname is not found(relid == 0) or same aliasname was used
* multiple times in a query(relid == -1)
*/
if (relid <= 0)
{
relids = NULL;
break;
}
if (bms_is_member(relid, relids))
{
hint_ereport(base->hint_str,
("Relation name \"%s\" is duplicated.", relname));
base->state = HINT_STATE_ERROR;
break;
}
relids = bms_add_member(relids, relid);
}
return relids;
}
/*
* Transform join method hint into handy form.
*
* - create bitmap of relids from alias names, to make it easier to check
* whether a join path matches a join method hint.
* - add join method hints which are necessary to enforce join order
* specified by Leading hint
*/
static bool
transform_join_hints(HintState *hstate, PlannerInfo *root, int nbaserel,
List *initial_rels, JoinMethodHint **join_method_hints)
{
int i;
int relid;
Relids joinrelids;
int njoinrels;
ListCell *l;
char *relname;
LeadingHint *lhint = NULL;
/*
* Create bitmap of relids from alias names for each join method hint.
* Bitmaps are more handy than strings in join searching.
*/
for (i = 0; i < hstate->num_hints[HINT_TYPE_JOIN_METHOD]; i++)
{
JoinMethodHint *hint = hstate->join_hints[i];
if (!hint_state_enabled(hint) || hint->nrels > nbaserel)
continue;
hint->joinrelids = create_bms_of_relids(&(hint->base), root,
initial_rels, hint->nrels, hint->relnames);
if (hint->joinrelids == NULL || hint->base.state == HINT_STATE_ERROR)
continue;
hstate->join_hint_level[hint->nrels] =
lappend(hstate->join_hint_level[hint->nrels], hint);
}
/*
* Create bitmap of relids from alias names for each rows hint.
* Bitmaps are more handy than strings in join searching.
*/
for (i = 0; i < hstate->num_hints[HINT_TYPE_ROWS]; i++)
{
RowsHint *hint = hstate->rows_hints[i];
if (!hint_state_enabled(hint) || hint->nrels > nbaserel)
continue;
hint->joinrelids = create_bms_of_relids(&(hint->base), root,
initial_rels, hint->nrels, hint->relnames);
}
/* Do nothing if no Leading hint was supplied. */
if (hstate->num_hints[HINT_TYPE_LEADING] == 0)
return false;
/*
* Decide whether to use Leading hint
*/
for (i = 0; i < hstate->num_hints[HINT_TYPE_LEADING]; i++)
{
LeadingHint *leading_hint = (LeadingHint *)hstate->leading_hint[i];
Relids relids;
if (leading_hint->base.state == HINT_STATE_ERROR)
continue;
relid = 0;
relids = NULL;
foreach(l, leading_hint->relations)
{
relname = (char *)lfirst(l);;
relid = find_relid_aliasname(root, relname, initial_rels,
leading_hint->base.hint_str);
if (relid == -1)
leading_hint->base.state = HINT_STATE_ERROR;
if (relid <= 0)
break;
if (bms_is_member(relid, relids))
{
hint_ereport(leading_hint->base.hint_str,
("Relation name \"%s\" is duplicated.", relname));
leading_hint->base.state = HINT_STATE_ERROR;
break;
}
relids = bms_add_member(relids, relid);
}
if (relid <= 0 || leading_hint->base.state == HINT_STATE_ERROR)
continue;
if (lhint != NULL)
{
hint_ereport(lhint->base.hint_str,
("Conflict %s hint.", HintTypeName[lhint->base.type]));
lhint->base.state = HINT_STATE_DUPLICATION;
}
leading_hint->base.state = HINT_STATE_USED;
lhint = leading_hint;
}
/* check to exist Leading hint marked with 'used'. */
if (lhint == NULL)
return false;
/*
* We need join method hints which fit specified join order in every join
* level. For example, Leading(A B C) virtually requires following join
* method hints, if no join method hint supplied:
* - level 1: none
* - level 2: NestLoop(A B), MergeJoin(A B), HashJoin(A B)
* - level 3: NestLoop(A B C), MergeJoin(A B C), HashJoin(A B C)
*
* If we already have join method hint which fits specified join order in
* that join level, we leave it as-is and don't add new hints.
*/
joinrelids = NULL;
njoinrels = 0;
if (lhint->outer_inner == NULL)
{
foreach(l, lhint->relations)
{
JoinMethodHint *hint;
relname = (char *)lfirst(l);
/*
* Find relid of the relation which has given name. If we have the
* name given in Leading hint multiple times in the join, nothing to
* do.
*/
relid = find_relid_aliasname(root, relname, initial_rels,
hstate->hint_str);
/* Create bitmap of relids for current join level. */
joinrelids = bms_add_member(joinrelids, relid);
njoinrels++;
/* We never have join method hint for single relation. */
if (njoinrels < 2)
continue;
/*
* If we don't have join method hint, create new one for the
* join combination with all join methods are enabled.
*/
hint = find_join_hint(joinrelids);
if (hint == NULL)
{
/*
* Here relnames is not set, since Relids bitmap is sufficient
* to control paths of this query afterward.
*/
hint = (JoinMethodHint *) JoinMethodHintCreate(
lhint->base.hint_str,
HINT_LEADING,
HINT_KEYWORD_LEADING);
hint->base.state = HINT_STATE_USED;
hint->nrels = njoinrels;
hint->enforce_mask = ENABLE_ALL_JOIN;
hint->joinrelids = bms_copy(joinrelids);
}
join_method_hints[njoinrels] = hint;
if (njoinrels >= nbaserel)
break;
}
bms_free(joinrelids);
if (njoinrels < 2)
return false;
/*
* Delete all join hints which have different combination from Leading
* hint.
*/
for (i = 2; i <= njoinrels; i++)
{
list_free(hstate->join_hint_level[i]);
hstate->join_hint_level[i] = lappend(NIL, join_method_hints[i]);
}
}
else
{
joinrelids = OuterInnerJoinCreate(lhint->outer_inner,
lhint,
root,
initial_rels,
hstate,
nbaserel);
njoinrels = bms_num_members(joinrelids);
Assert(njoinrels >= 2);
/*
* Delete all join hints which have different combination from Leading
* hint.
*/
for (i = 2;i <= njoinrels; i++)
{
if (hstate->join_hint_level[i] != NIL)
{
foreach(l, hstate->join_hint_level[i]) {
JoinMethodHint *hint = (JoinMethodHint *)lfirst(l);
if (hint->inner_nrels == 0 &&
!(bms_intersect(hint->joinrelids, joinrelids) == NULL ||
bms_equal(bms_union(hint->joinrelids, joinrelids),
hint->joinrelids)))
{
hstate->join_hint_level[i] =
foreach_delete_current(hstate->join_hint_level[i], l);
}
}
}
}
bms_free(joinrelids);
}
if (hint_state_enabled(lhint))
{
set_join_config_options(DISABLE_ALL_JOIN, current_hint_state->context);
return true;
}
return false;
}
/*
* Generate a normalized version of the query string that will be used to
* represent all similar queries.
*
* Note that the normalized representation may well vary depending on
* just which "equivalent" query is used to create the hashtable entry.
* We assume this is OK.
*
* If query_loc > 0, then "query" has been advanced by that much compared to
* the original string start, so we need to translate the provided locations
* to compensate. (This lets us avoid re-scanning statements before the one
* of interest, so it's worth doing.)
*
* *query_len_p contains the input string length, and is updated with
* the result string length on exit. The resulting string might be longer
* or shorter depending on what happens with replacement of constants.
*
* Returns a palloc'd string.
*/
static char *
generate_normalized_query(JumbleState *jstate, const char *query,
int query_loc, int *query_len_p, int encoding)
{
char *norm_query;
int query_len = *query_len_p;
int i,
norm_query_buflen, /* Space allowed for norm_query */
len_to_wrt, /* Length (in bytes) to write */
quer_loc = 0, /* Source query byte location */
n_quer_loc = 0, /* Normalized query byte location */
last_off = 0, /* Offset from start for previous tok */
last_tok_len = 0; /* Length (in bytes) of that tok */
/*
* Get constants' lengths (core system only gives us locations). Note
* this also ensures the items are sorted by location.
*/
fill_in_constant_lengths(jstate, query, query_loc);
/*
* Allow for $n symbols to be longer than the constants they replace.
* Constants must take at least one byte in text form, while a $n symbol
* certainly isn't more than 11 bytes, even if n reaches INT_MAX. We
* could refine that limit based on the max value of n for the current
* query, but it hardly seems worth any extra effort to do so.
*/
norm_query_buflen = query_len + jstate->clocations_count * 10;
/* Allocate result buffer */
norm_query = palloc(norm_query_buflen + 1);
for (i = 0; i < jstate->clocations_count; i++)
{
int off, /* Offset from start for cur tok */
tok_len; /* Length (in bytes) of that tok */
off = jstate->clocations[i].location;
/* Adjust recorded location if we're dealing with partial string */
off -= query_loc;
tok_len = jstate->clocations[i].length;
if (tok_len < 0)
continue; /* ignore any duplicates */
/* Copy next chunk (what precedes the next constant) */
len_to_wrt = off - last_off;
len_to_wrt -= last_tok_len;
Assert(len_to_wrt >= 0);
memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
n_quer_loc += len_to_wrt;
/*
* PG_HINT_PLAN: DON'T TAKE IN a6f22e8356 so that the designed behavior
* is kept stable.
*/
/* And insert a '?' in place of the constant token */
norm_query[n_quer_loc++] = '?';
quer_loc = off + tok_len;
last_off = off;
last_tok_len = tok_len;
}
/*
* We've copied up until the last ignorable constant. Copy over the
* remaining bytes of the original query string.
*/
len_to_wrt = query_len - quer_loc;
Assert(len_to_wrt >= 0);
memcpy(norm_query + n_quer_loc, query + quer_loc, len_to_wrt);
n_quer_loc += len_to_wrt;
Assert(n_quer_loc <= norm_query_buflen);
norm_query[n_quer_loc] = '\0';
*query_len_p = n_quer_loc;
return norm_query;
}
/*
* Given a valid SQL string and an array of constant-location records,
* fill in the textual lengths of those constants.
*
* The constants may use any allowed constant syntax, such as float literals,
* bit-strings, single-quoted strings and dollar-quoted strings. This is
* accomplished by using the public API for the core scanner.
*
* It is the caller's job to ensure that the string is a valid SQL statement
* with constants at the indicated locations. Since in practice the string
* has already been parsed, and the locations that the caller provides will
* have originated from within the authoritative parser, this should not be
* a problem.
*
* Duplicate constant pointers are possible, and will have their lengths
* marked as '-1', so that they are later ignored. (Actually, we assume the
* lengths were initialized as -1 to start with, and don't change them here.)
*
* If query_loc > 0, then "query" has been advanced by that much compared to
* the original string start, so we need to translate the provided locations
* to compensate. (This lets us avoid re-scanning statements before the one
* of interest, so it's worth doing.)
*
* N.B. There is an assumption that a '-' character at a Const location begins
* a negative numeric constant. This precludes there ever being another
* reason for a constant to start with a '-'.
*/
static void
fill_in_constant_lengths(JumbleState *jstate, const char *query,
int query_loc)
{
LocationLen *locs;
core_yyscan_t yyscanner;
core_yy_extra_type yyextra;
core_YYSTYPE yylval;
YYLTYPE yylloc;
int last_loc = -1;
int i;
/*
* Sort the records by location so that we can process them in order while
* scanning the query text.
*/
if (jstate->clocations_count > 1)
qsort(jstate->clocations, jstate->clocations_count,
sizeof(LocationLen), comp_location);
locs = jstate->clocations;
/* initialize the flex scanner --- should match raw_parser() */
yyscanner = scanner_init(query,
&yyextra,
&ScanKeywords,
ScanKeywordTokens);
/* we don't want to re-emit any escape string warnings */
yyextra.escape_string_warning = false;
/* Search for each constant, in sequence */
for (i = 0; i < jstate->clocations_count; i++)
{
int loc = locs[i].location;
int tok;
/* Adjust recorded location if we're dealing with partial string */
loc -= query_loc;
Assert(loc >= 0);
if (loc <= last_loc)
continue; /* Duplicate constant, ignore */
/* Lex tokens until we find the desired constant */
for (;;)
{
tok = core_yylex(&yylval, &yylloc, yyscanner);
/* We should not hit end-of-string, but if we do, behave sanely */
if (tok == 0)
break; /* out of inner for-loop */
/*
* We should find the token position exactly, but if we somehow
* run past it, work with that.
*/
if (yylloc >= loc)
{
if (query[loc] == '-')
{
/*
* It's a negative value - this is the one and only case
* where we replace more than a single token.
*
* Do not compensate for the core system's special-case
* adjustment of location to that of the leading '-'
* operator in the event of a negative constant. It is
* also useful for our purposes to start from the minus
* symbol. In this way, queries like "select * from foo
* where bar = 1" and "select * from foo where bar = -2"
* will have identical normalized query strings.
*/
tok = core_yylex(&yylval, &yylloc, yyscanner);
if (tok == 0)
break; /* out of inner for-loop */
}
/*
* We now rely on the assumption that flex has placed a zero
* byte after the text of the current token in scanbuf.
*/
locs[i].length = strlen(yyextra.scanbuf + loc);
break; /* out of inner for-loop */
}
}
/* If we hit end-of-string, give up, leaving remaining lengths -1 */
if (tok == 0)
break;
last_loc = loc;
}
scanner_finish(yyscanner);
}
/*
* comp_location: comparator for qsorting LocationLen structs by location
*/
static int
comp_location(const void *a, const void *b)
{
int l = ((const LocationLen *) a)->location;
int r = ((const LocationLen *) b)->location;
if (l < r)
return -1;
else if (l > r)
return +1;
else
return 0;
}
/*
* hook of make_join_rel()
*
* call make_join_rel() after changing enable_* parameters according to given
* hints.
*/
static RelOptInfo *
pg_hint_plan_make_join_rel(PlannerInfo *root, RelOptInfo *rel1, RelOptInfo *rel2)
{
Relids joinrelids;
JoinMethodHint *hint;
RelOptInfo *rel;
int save_nestlevel;
if (!current_hint_state) {
return prev_make_join_rel_hook ? prev_make_join_rel_hook(root, rel1, rel2) : make_join_relation(root, rel1, rel2);
}
joinrelids = bms_union(rel1->relids, rel2->relids);
hint = find_join_hint(joinrelids);
bms_free(joinrelids);
if (!hint)
return prev_make_join_rel_hook ? prev_make_join_rel_hook(root, rel1, rel2) : make_join_relation(root, rel1, rel2);
if (hint->inner_nrels == 0)
{
save_nestlevel = NewGUCNestLevel();
set_join_config_options(hint->enforce_mask,
current_hint_state->context);
rel = prev_make_join_rel_hook ? prev_make_join_rel_hook(root, rel1, rel2) : make_join_relation(root, rel1, rel2);
hint->base.state = HINT_STATE_USED;
/*
* Restore the GUC variables we set above.
*/
AtEOXact_GUC(true, save_nestlevel);
}
else
rel = prev_make_join_rel_hook ? prev_make_join_rel_hook(root, rel1, rel2) : make_join_relation(root, rel1, rel2);
return rel;
}
static void
pg_hint_plan_add_paths_to_joinrel(PlannerInfo *root,
RelOptInfo *joinrel,
RelOptInfo *outerrel,
RelOptInfo *innerrel,
JoinType jointype,
SpecialJoinInfo *sjinfo,
List *restrictlist)
{
Relids joinrelids;
JoinMethodHint *join_hint;
int save_nestlevel;
// no hint
if (!current_hint_state) {
if(prev_add_paths_to_joinrel_hook) {
prev_add_paths_to_joinrel_hook(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
} else {
add_paths_to_join_relation(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
}
return;
}
joinrelids = bms_union(outerrel->relids, innerrel->relids);
join_hint = find_join_hint(joinrelids);
bms_free(joinrelids);
if (join_hint && join_hint->inner_nrels != 0)
{
save_nestlevel = NewGUCNestLevel();
if (bms_equal(join_hint->inner_joinrelids, innerrel->relids))
{
set_join_config_options(join_hint->enforce_mask,
current_hint_state->context);
if(prev_add_paths_to_joinrel_hook) {
prev_add_paths_to_joinrel_hook(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
} else {
add_paths_to_join_relation(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
}
join_hint->base.state = HINT_STATE_USED;
}
else
{
set_join_config_options(DISABLE_ALL_JOIN,
current_hint_state->context);
if(prev_add_paths_to_joinrel_hook) {
prev_add_paths_to_joinrel_hook(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
} else {
add_paths_to_join_relation(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
}
}
/*
* Restore the GUC variables we set above.
*/
AtEOXact_GUC(true, save_nestlevel);
}
else {
if(prev_add_paths_to_joinrel_hook) {
prev_add_paths_to_joinrel_hook(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
} else {
add_paths_to_join_relation(root, joinrel, outerrel, innerrel, jointype,
sjinfo, restrictlist);
}
}
}
static int
get_num_baserels(List *initial_rels)
{
int nbaserel = 0;
ListCell *l;
foreach(l, initial_rels)
{
RelOptInfo *rel = (RelOptInfo *) lfirst(l);
if (rel->reloptkind == RELOPT_BASEREL)
nbaserel++;
else if (rel->reloptkind ==RELOPT_JOINREL)
nbaserel+= bms_num_members(rel->relids);
else
{
/* other values not expected here */
elog(ERROR, "unrecognized reloptkind type: %d", rel->reloptkind);
}
}
return nbaserel;
}
static RelOptInfo *
pg_hint_plan_join_search(PlannerInfo *root, int levels_needed,
List *initial_rels)
{
JoinMethodHint **join_method_hints;
int nbaserel;
RelOptInfo *rel;
int i;
bool leading_hint_enable;
/*
* Use standard planner (or geqo planner) if pg_hint_plan is disabled or no
* valid hint is supplied or current nesting depth is nesting depth of SPI
* calls.
*/
if (!current_hint_state || hint_inhibit_level > 0)
{
if (prev_join_search)
return (*prev_join_search) (root, levels_needed, initial_rels);
#if 0
else if (enable_geqo && levels_needed >= geqo_threshold)
return geqo(root, levels_needed, initial_rels);
#endif
else
return standard_join_search(root, levels_needed, initial_rels);
}
#if 0
/*
* In the case using GEQO, only scan method hints and Set hints have
* effect. Join method and join order is not controllable by hints.
*/
if (enable_geqo && levels_needed >= geqo_threshold)
return geqo(root, levels_needed, initial_rels);
#endif
nbaserel = get_num_baserels(initial_rels);
current_hint_state->join_hint_level =
palloc0(sizeof(List *) * (nbaserel + 1));
join_method_hints = palloc0(sizeof(JoinMethodHint *) * (nbaserel + 1));
leading_hint_enable = transform_join_hints(current_hint_state,
root, nbaserel,
initial_rels, join_method_hints);
rel = standard_join_search(root, levels_needed, initial_rels);
/*
* Adjust number of parallel workers of the result rel to the largest
* number of the component paths.
*/
if (current_hint_state->num_hints[HINT_TYPE_PARALLEL] > 0)
{
ListCell *lc;
int nworkers = 0;
foreach (lc, initial_rels)
{
ListCell *lcp;
RelOptInfo *initrel = (RelOptInfo *) lfirst(lc);
foreach (lcp, initrel->partial_pathlist)
{
Path *path = (Path *) lfirst(lcp);
if (nworkers < path-> parallel_workers)
nworkers = path-> parallel_workers;
}
}
foreach (lc, rel->partial_pathlist)
{
Path *path = (Path *) lfirst(lc);
if (path->parallel_safe && path->parallel_workers < nworkers)
path->parallel_workers = nworkers;
}
}
for (i = 2; i <= nbaserel; i++)
{
list_free(current_hint_state->join_hint_level[i]);
/* free Leading hint only */
if (join_method_hints[i] != NULL &&
join_method_hints[i]->enforce_mask == ENABLE_ALL_JOIN)
JoinMethodHintDelete(join_method_hints[i]);
}
pfree(current_hint_state->join_hint_level);
pfree(join_method_hints);
if (leading_hint_enable)
set_join_config_options(current_hint_state->init_join_mask,
current_hint_state->context);
return rel;
}
static void
set_plain_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, RangeTblEntry *rte)
{
Relids required_outer;
/*
* We don't support pushing join clauses into the quals of a seqscan, but
* it could still have required parameterization due to LATERAL refs in
* its tlist.
*/
required_outer = rel->lateral_relids;
/* Consider sequential scan */
add_path(rel, create_seqscan_path(root, rel, required_outer, 0), root);
/* If appropriate, consider parallel sequential scan */
if (rel->consider_parallel && required_outer == NULL)
create_plain_partial_paths(root, rel);
/* Consider index scans */
create_index_paths(root, rel);
/* Consider TID scans */
create_tidscan_paths(root, rel);
}
/*
* Force number of wokers if instructed by hint
*/
void
pg_hint_plan_set_rel_pathlist(PlannerInfo * root, RelOptInfo *rel,
Index rti, RangeTblEntry *rte)
{
ParallelHint *phint;
ListCell *l;
int found_hints;
/* call the previous hook */
if (prev_set_rel_pathlist)
prev_set_rel_pathlist(root, rel, rti, rte);
/* Nothing to do if no hint available */
if (current_hint_state == NULL)
return;
/* Don't touch dummy rels. */
if (IS_DUMMY_REL(rel))
return;
/*
* We can accept only plain relations, foreign tables and table saples are
* also unacceptable. See set_rel_pathlist.
*/
if ((rel->rtekind != RTE_RELATION &&
rel->rtekind != RTE_SUBQUERY)||
rte->relkind == RELKIND_FOREIGN_TABLE ||
rte->tablesample != NULL)
return;
/*
* Even though UNION ALL node doesn't have particular name so usually it is
* unhintable, turn on parallel when it contains parallel nodes.
*/
if (rel->rtekind == RTE_SUBQUERY)
{
ListCell *lc;
bool inhibit_nonparallel = false;
if (rel->partial_pathlist == NIL)
return;
foreach(lc, rel->partial_pathlist)
{
ListCell *lcp;
AppendPath *apath = (AppendPath *) lfirst(lc);
int parallel_workers = 0;
if (!IsA(apath, AppendPath))
continue;
foreach (lcp, apath->subpaths)
{
Path *spath = (Path *) lfirst(lcp);
if (spath->parallel_aware &&
parallel_workers < spath->parallel_workers)
parallel_workers = spath->parallel_workers;
}
apath->path.parallel_workers = parallel_workers;
inhibit_nonparallel = true;
}
if (inhibit_nonparallel)
{
ListCell *lcr;
foreach(lcr, rel->pathlist)
{
Path *path = (Path *) lfirst(lcr);
if (path->startup_cost < disable_cost)
{
path->startup_cost += disable_cost;
path->total_cost += disable_cost;
}
}
}
return;
}
/* We cannot handle if this requires an outer */
if (rel->lateral_relids)
return;
/* Return if this relation gets no enfocement */
if ((found_hints = setup_hint_enforcement(root, rel, NULL, &phint)) == 0)
return;
/* Here, we regenerate paths with the current hint restriction */
if (found_hints & HINT_BM_SCAN_METHOD || found_hints & HINT_BM_PARALLEL)
{
/*
* When hint is specified on non-parent relations, discard existing
* paths and regenerate based on the hint considered. Otherwise we
* already have hinted childx paths then just adjust the number of
* planned number of workers.
*/
if (root->simple_rte_array[rel->relid]->inh)
{
/* enforce number of workers if requested */
if (phint && phint->force_parallel)
{
if (phint->nworkers == 0)
{
list_free_deep(rel->partial_pathlist);
rel->partial_pathlist = NIL;
}
else
{
/* prioritize partial paths */
foreach (l, rel->partial_pathlist)
{
Path *ppath = (Path *) lfirst(l);
if (ppath->parallel_safe)
{
ppath->parallel_workers = phint->nworkers;
ppath->startup_cost = 0;
ppath->total_cost = 0;
}
}
/* disable non-partial paths */
foreach (l, rel->pathlist)
{
Path *ppath = (Path *) lfirst(l);
if (ppath->startup_cost < disable_cost)
{
ppath->startup_cost += disable_cost;
ppath->total_cost += disable_cost;
}
}
}
}
}
else
{
/* Just discard all the paths considered so far */
list_free_deep(rel->pathlist);
rel->pathlist = NIL;
list_free_deep(rel->partial_pathlist);
rel->partial_pathlist = NIL;
/* Regenerate paths with the current enforcement */
set_plain_rel_pathlist(root, rel, rte);
/* Additional work to enforce parallel query execution */
if (phint && phint->nworkers > 0)
{
/*
* For Parallel Append to be planned properly, we shouldn't set
* the costs of non-partial paths to disable-value. Lower the
* priority of non-parallel paths by setting partial path costs
* to 0 instead.
*/
foreach (l, rel->partial_pathlist)
{
Path *path = (Path *) lfirst(l);
path->startup_cost = 0;
path->total_cost = 0;
}
/* enforce number of workers if requested */
if (phint->force_parallel)
{
foreach (l, rel->partial_pathlist)
{
Path *ppath = (Path *) lfirst(l);
if (ppath->parallel_safe)
ppath->parallel_workers = phint->nworkers;
}
}
/* Generate gather paths */
if (rel->reloptkind == RELOPT_BASEREL &&
bms_membership(root->all_baserels) != BMS_SINGLETON)
generate_gather_paths(root, rel, false);
}
}
}
reset_hint_enforcement();
}
/*
* stmt_beg callback is called when each query in PL/pgSQL function is about
* to be executed. At that timing, we save query string in the global variable
* plpgsql_query_string to use it in planner hook. It's safe to use one global
* variable for the purpose, because its content is only necessary until
* planner hook is called for the query, so recursive PL/pgSQL function calls
* don't harm this mechanism.
*/
static void
pg_hint_plan_plpgsql_stmt_beg(PLpgSQL_execstate *estate, PLpgSQL_stmt *stmt)
{
plpgsql_recurse_level++;
}
/*
* stmt_end callback is called then each query in PL/pgSQL function has
* finished. At that timing, we clear plpgsql_query_string to tell planner
* hook that next call is not for a query written in PL/pgSQL block.
*/
static void
pg_hint_plan_plpgsql_stmt_end(PLpgSQL_execstate *estate, PLpgSQL_stmt *stmt)
{
/*
* If we come here, we should have gone through the statement begin
* callback at least once.
*/
if (plpgsql_recurse_level > 0)
plpgsql_recurse_level--;
}
void plpgsql_query_erase_callback(ResourceReleasePhase phase,
bool isCommit,
bool isTopLevel,
void *arg)
{
/* Cleanup is just applied once all the locks are released */
if (phase != RESOURCE_RELEASE_AFTER_LOCKS)
return;
if (isTopLevel)
{
/* Cancel recurse level */
plpgsql_recurse_level = 0;
}
else if (plpgsql_recurse_level > 0)
{
/*
* This applies when a transaction is aborted for a PL/pgSQL query,
* like when a transaction triggers an exception, or for an internal
* commit.
*/
plpgsql_recurse_level--;
}
}
#ifdef USE_ORCA
/*
* This function hook allows external code (i.e. backend) to parse a query into
* hint structures.
*/
static void *
external_plan_hint_hook(Query *parse)
{
if (parse == NULL)
return NULL;
current_hint_retrieved = false;
get_current_hint_string(NULL, parse);
if (!current_hint_str)
return NULL;
if(hstate)
hstate->log_level = debug_level;
return hstate;
}
#endif