in sql/opt_explain_json.cc [1508:1834]
bool Explain_format_JSON::begin_context(Explain_context_enum ctx,
SELECT_LEX_UNIT *subquery,
const Explain_format_flags *flags)
{
using namespace opt_explain_json_namespace;
context *prev_context= current_context;
switch(ctx) {
case CTX_JOIN:
DBUG_ASSERT(current_context == NULL ||
// subqueries:
current_context->type == CTX_SELECT_LIST ||
current_context->type == CTX_UPDATE_VALUE_LIST ||
current_context->type == CTX_DERIVED ||
current_context->type == CTX_OPTIMIZED_AWAY_SUBQUERY ||
current_context->type == CTX_WHERE ||
current_context->type == CTX_HAVING ||
current_context->type == CTX_ORDER_BY_SQ ||
current_context->type == CTX_GROUP_BY_SQ ||
current_context->type == CTX_QUERY_SPEC);
if ((current_context=
new join_ctx(CTX_JOIN, K_QUERY_BLOCK, current_context)) == NULL)
return true;
break;
case CTX_ORDER_BY:
{
DBUG_ASSERT(current_context->type == CTX_JOIN);
sort_ctx *ctx= new sort_with_subqueries_ctx(CTX_ORDER_BY,
K_ORDERING_OPERATION,
current_context,
SQ_ORDER_BY, flags,
ESC_ORDER_BY);
if (ctx == NULL)
return true;
current_context->set_sort(ctx);
current_context= ctx;
break;
}
case CTX_GROUP_BY:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT);
sort_ctx *ctx= new sort_with_subqueries_ctx(CTX_GROUP_BY,
K_GROUPING_OPERATION,
current_context,
SQ_GROUP_BY, flags,
ESC_GROUP_BY);
if (ctx == NULL)
return true;
current_context->set_sort(ctx);
current_context= ctx;
break;
}
case CTX_DISTINCT:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_ORDER_BY);
sort_ctx *ctx= new sort_ctx(CTX_DISTINCT, K_DUPLICATES_REMOVAL,
current_context, flags, ESC_DISTINCT);
if (ctx == NULL)
return true;
current_context->set_sort(ctx);
current_context= ctx;
break;
}
case CTX_BUFFER_RESULT:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT ||
current_context->type == CTX_GROUP_BY);
sort_ctx *ctx= new sort_ctx(CTX_BUFFER_RESULT, K_BUFFER_RESULT,
current_context, flags, ESC_BUFFER_RESULT);
if (ctx == NULL)
return true;
current_context->set_sort(ctx);
current_context= ctx;
break;
}
case CTX_JOIN_TAB:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_MATERIALIZATION ||
current_context->type == CTX_DUPLICATES_WEEDOUT ||
current_context->type == CTX_GROUP_BY ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT ||
current_context->type == CTX_BUFFER_RESULT ||
current_context->type == CTX_SIMPLE_GROUP_BY ||
current_context->type == CTX_SIMPLE_ORDER_BY ||
current_context->type == CTX_SIMPLE_DISTINCT);
join_tab_ctx *ctx= new join_tab_ctx(CTX_JOIN_TAB, current_context);
if (ctx == NULL || current_context->add_join_tab(ctx))
return true;
current_context= ctx;
break;
}
case CTX_SIMPLE_ORDER_BY:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_MATERIALIZATION ||
current_context->type == CTX_DUPLICATES_WEEDOUT ||
current_context->type == CTX_GROUP_BY ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_BUFFER_RESULT ||
current_context->type == CTX_DISTINCT);
simple_sort_ctx *ctx=
new simple_sort_with_subqueries_ctx(CTX_SIMPLE_ORDER_BY,
K_ORDERING_OPERATION,
current_context, SQ_ORDER_BY, flags,
ESC_ORDER_BY);
if (ctx == NULL || current_context->add_join_tab(ctx))
return true;
current_context= ctx;
break;
}
case CTX_SIMPLE_GROUP_BY:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_MATERIALIZATION ||
current_context->type == CTX_DUPLICATES_WEEDOUT ||
current_context->type == CTX_GROUP_BY ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT ||
current_context->type == CTX_BUFFER_RESULT ||
current_context->type == CTX_SIMPLE_ORDER_BY ||
current_context->type == CTX_SIMPLE_DISTINCT);
simple_sort_ctx *ctx=
new simple_sort_with_subqueries_ctx(CTX_SIMPLE_GROUP_BY,
K_GROUPING_OPERATION,
current_context, SQ_GROUP_BY, flags,
ESC_GROUP_BY);
if (ctx == NULL || current_context->add_join_tab(ctx))
return true;
current_context= ctx;
break;
}
case CTX_SIMPLE_DISTINCT:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_MATERIALIZATION ||
current_context->type == CTX_DUPLICATES_WEEDOUT ||
current_context->type == CTX_GROUP_BY ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT ||
current_context->type == CTX_BUFFER_RESULT ||
current_context->type == CTX_SIMPLE_ORDER_BY);
simple_sort_ctx *ctx=
new simple_sort_ctx(CTX_SIMPLE_DISTINCT, K_DUPLICATES_REMOVAL,
current_context, flags, ESC_DISTINCT);
if (ctx == NULL || current_context->add_join_tab(ctx))
return true;
current_context= ctx;
break;
}
case CTX_MATERIALIZATION:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_GROUP_BY ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT ||
current_context->type == CTX_BUFFER_RESULT ||
current_context->type == CTX_DUPLICATES_WEEDOUT);
materialize_ctx *ctx= new materialize_ctx(current_context);
if (ctx == NULL || current_context->add_join_tab(ctx))
return true;
current_context= ctx;
break;
}
case CTX_DUPLICATES_WEEDOUT:
{
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_GROUP_BY ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT ||
current_context->type == CTX_BUFFER_RESULT ||
current_context->type == CTX_MATERIALIZATION);
duplication_weedout_ctx *ctx=
new duplication_weedout_ctx(current_context);
if (ctx == NULL || current_context->add_join_tab(ctx))
return true;
current_context= ctx;
break;
}
case CTX_SELECT_LIST:
{
subquery_ctx *ctx= new subquery_ctx(CTX_SELECT_LIST, NULL,
current_context);
if (ctx == NULL ||
current_context->add_subquery(SQ_SELECT_LIST, ctx))
return true;
current_context= ctx;
break;
}
case CTX_UPDATE_VALUE_LIST:
{
subquery_ctx *ctx= new subquery_ctx(CTX_UPDATE_VALUE_LIST, NULL,
current_context);
if (ctx == NULL ||
current_context->add_subquery(SQ_UPDATE_VALUE, ctx))
return true;
current_context= ctx;
break;
}
case CTX_DERIVED:
{
current_context= new subquery_ctx(CTX_DERIVED,
K_MATERIALIZED_FROM_SUBQUERY,
current_context);
if (current_context == NULL)
return true;
break;
}
case CTX_OPTIMIZED_AWAY_SUBQUERY:
{
subquery_ctx *ctx= new subquery_ctx(CTX_OPTIMIZED_AWAY_SUBQUERY, NULL,
current_context);
if (ctx == NULL || current_context->add_subquery(SQ_HOMELESS, ctx))
return true;
current_context= ctx;
break;
}
case CTX_WHERE:
{
DBUG_ASSERT(subquery != NULL);
subquery_ctx *ctx= new subquery_ctx(CTX_WHERE, NULL, current_context);
if (ctx == NULL ||
current_context->add_where_subquery(ctx, subquery))
return true;
current_context= ctx;
break;
}
case CTX_HAVING:
{
subquery_ctx *ctx= new subquery_ctx(CTX_HAVING, NULL, current_context);
if (ctx == NULL || current_context->add_subquery(SQ_HAVING, ctx))
return true;
current_context= ctx;
break;
}
case CTX_ORDER_BY_SQ:
{
subquery_ctx *ctx= new subquery_ctx(CTX_ORDER_BY_SQ, NULL,
current_context);
if (ctx == NULL || current_context->add_subquery(SQ_ORDER_BY, ctx))
return true;
current_context= ctx;
break;
}
case CTX_GROUP_BY_SQ:
{
subquery_ctx *ctx= new subquery_ctx(CTX_GROUP_BY_SQ, NULL,
current_context);
if (ctx == NULL || current_context->add_subquery(SQ_GROUP_BY, ctx))
return true;
current_context= ctx;
break;
}
case CTX_UNION:
DBUG_ASSERT(current_context == NULL ||
// subqueries:
current_context->type == CTX_SELECT_LIST ||
current_context->type == CTX_UPDATE_VALUE_LIST ||
current_context->type == CTX_DERIVED ||
current_context->type == CTX_OPTIMIZED_AWAY_SUBQUERY ||
current_context->type == CTX_WHERE ||
current_context->type == CTX_HAVING ||
current_context->type == CTX_ORDER_BY_SQ ||
current_context->type == CTX_GROUP_BY_SQ ||
current_context->type == CTX_QUERY_SPEC);
current_context= new union_ctx(current_context);
if (current_context == NULL)
return true;
break;
case CTX_UNION_RESULT:
{
DBUG_ASSERT(current_context->type == CTX_UNION);
union_result_ctx *ctx= new union_result_ctx(current_context);
if (ctx == NULL)
return true;
current_context->set_union_result(ctx);
current_context= ctx;
break;
}
case CTX_QUERY_SPEC:
{
DBUG_ASSERT(current_context->type == CTX_UNION);
subquery_ctx *ctx= new subquery_ctx(CTX_QUERY_SPEC, NULL,
current_context);
if (ctx == NULL || current_context->add_query_spec(ctx))
return true;
current_context= ctx;
break;
}
case CTX_MESSAGE:
{
/*
Like CTX_JOIN_TAB:
*/
DBUG_ASSERT(current_context->type == CTX_JOIN ||
current_context->type == CTX_MATERIALIZATION ||
current_context->type == CTX_DUPLICATES_WEEDOUT ||
current_context->type == CTX_GROUP_BY ||
current_context->type == CTX_ORDER_BY ||
current_context->type == CTX_DISTINCT ||
current_context->type == CTX_BUFFER_RESULT ||
current_context->type == CTX_SIMPLE_GROUP_BY ||
current_context->type == CTX_SIMPLE_ORDER_BY ||
current_context->type == CTX_SIMPLE_DISTINCT);
joinable_ctx *ctx= new message_ctx(current_context);
if (ctx == NULL || current_context->add_join_tab(ctx))
return true;
current_context= ctx;
break;
}
default:
DBUG_ASSERT(!"Unknown EXPLAIN context!");
return true;
}
if (prev_context)
prev_context->set_child(current_context);
return false;
}