in exec/java-exec/src/main/java/org/apache/drill/exec/planner/logical/DrillFilterJoinRules.java [126:349]
private static void splitJoinCondition(
List<RelDataTypeField> sysFieldList,
List<RelNode> inputs,
RexNode condition,
List<List<RexNode>> joinKeys,
List<Integer> filterNulls,
List<SqlOperator> rangeOp,
List<RexNode> nonEquiList) {
final int sysFieldCount = sysFieldList.size();
final RelOptCluster cluster = inputs.get(0).getCluster();
final RexBuilder rexBuilder = cluster.getRexBuilder();
final RelDataTypeFactory typeFactory = cluster.getTypeFactory();
final ImmutableBitSet[] inputsRange = new ImmutableBitSet[inputs.size()];
int totalFieldCount = 0;
for (int i = 0; i < inputs.size(); i++) {
final int firstField = totalFieldCount + sysFieldCount;
totalFieldCount = firstField + inputs.get(i).getRowType().getFieldCount();
inputsRange[i] = ImmutableBitSet.range(firstField, totalFieldCount);
}
// adjustment array
int[] adjustments = new int[totalFieldCount];
for (int i = 0; i < inputs.size(); i++) {
final int adjustment = inputsRange[i].nextSetBit(0);
for (int j = adjustment; j < inputsRange[i].length(); j++) {
adjustments[j] = -adjustment;
}
}
if (condition.getKind() == SqlKind.AND) {
for (RexNode operand : ((RexCall) condition).getOperands()) {
splitJoinCondition(
sysFieldList,
inputs,
operand,
joinKeys,
filterNulls,
rangeOp,
nonEquiList);
}
return;
}
if (condition instanceof RexCall) {
RexNode leftKey = null;
RexNode rightKey = null;
int leftInput = 0;
int rightInput = 0;
List<RelDataTypeField> leftFields = null;
List<RelDataTypeField> rightFields = null;
boolean reverse = false;
final RexCall call =
collapseExpandedIsNotDistinctFromExpr((RexCall) condition, rexBuilder);
SqlKind kind = call.getKind();
// Only consider range operators if we haven't already seen one
if ((kind == SqlKind.EQUALS)
|| (filterNulls != null
&& kind == SqlKind.IS_NOT_DISTINCT_FROM)
|| (rangeOp != null
&& rangeOp.isEmpty()
&& (kind == SqlKind.GREATER_THAN
|| kind == SqlKind.GREATER_THAN_OR_EQUAL
|| kind == SqlKind.LESS_THAN
|| kind == SqlKind.LESS_THAN_OR_EQUAL))) {
final List<RexNode> operands = call.getOperands();
RexNode op0 = operands.get(0);
RexNode op1 = operands.get(1);
final ImmutableBitSet projRefs0 = RelOptUtil.InputFinder.bits(op0);
final ImmutableBitSet projRefs1 = RelOptUtil.InputFinder.bits(op1);
boolean foundBothInputs = false;
for (int i = 0; i < inputs.size() && !foundBothInputs; i++) {
if (projRefs0.intersects(inputsRange[i])
&& projRefs0.union(inputsRange[i]).equals(inputsRange[i])) {
if (leftKey == null) {
leftKey = op0;
leftInput = i;
leftFields = inputs.get(leftInput).getRowType().getFieldList();
} else {
rightKey = op0;
rightInput = i;
rightFields = inputs.get(rightInput).getRowType().getFieldList();
reverse = true;
foundBothInputs = true;
}
} else if (projRefs1.intersects(inputsRange[i])
&& projRefs1.union(inputsRange[i]).equals(inputsRange[i])) {
if (leftKey == null) {
leftKey = op1;
leftInput = i;
leftFields = inputs.get(leftInput).getRowType().getFieldList();
} else {
rightKey = op1;
rightInput = i;
rightFields = inputs.get(rightInput).getRowType().getFieldList();
foundBothInputs = true;
}
}
}
if ((leftKey != null) && (rightKey != null)) {
// replace right Key input ref
rightKey =
rightKey.accept(
new RelOptUtil.RexInputConverter(
rexBuilder,
rightFields,
rightFields,
adjustments));
// left key only needs to be adjusted if there are system
// fields, but do it for uniformity
leftKey =
leftKey.accept(
new RelOptUtil.RexInputConverter(
rexBuilder,
leftFields,
leftFields,
adjustments));
RelDataType leftKeyType = leftKey.getType();
RelDataType rightKeyType = rightKey.getType();
if (leftKeyType != rightKeyType) {
// perform casting
RelDataType targetKeyType =
typeFactory.leastRestrictive(
Arrays.asList(leftKeyType, rightKeyType));
if (targetKeyType == null) {
throw new AssertionError("Cannot find common type for join keys "
+ leftKey + " (type " + leftKeyType + ") and " + rightKey
+ " (type " + rightKeyType + ")");
}
if (leftKeyType != targetKeyType) {
leftKey =
rexBuilder.makeCast(targetKeyType, leftKey);
}
if (rightKeyType != targetKeyType) {
rightKey =
rexBuilder.makeCast(targetKeyType, rightKey);
}
}
}
}
if ((rangeOp == null)
&& ((leftKey == null) || (rightKey == null))) {
// no equality join keys found yet:
// try transforming the condition to
// equality "join" conditions, e.g.
// f(LHS) > 0 ===> ( f(LHS) > 0 ) = TRUE,
// and make the RHS produce TRUE, but only if we're strictly
// looking for equi-joins
final ImmutableBitSet projRefs = RelOptUtil.InputFinder.bits(condition);
leftKey = null;
rightKey = null;
boolean foundInput = false;
for (int i = 0; i < inputs.size() && !foundInput; i++) {
if (inputsRange[i].contains(projRefs)) {
leftInput = i;
leftFields = inputs.get(leftInput).getRowType().getFieldList();
leftKey = condition.accept(
new RelOptUtil.RexInputConverter(
rexBuilder,
leftFields,
leftFields,
adjustments));
rightKey = rexBuilder.makeLiteral(true);
// effectively performing an equality comparison
kind = SqlKind.EQUALS;
foundInput = true;
}
}
}
if ((leftKey != null) && (rightKey != null)) {
// found suitable join keys
// add them to key list, ensuring that if there is a
// non-equi join predicate, it appears at the end of the
// key list; also mark the null filtering property
addJoinKey(
joinKeys.get(leftInput),
leftKey,
(rangeOp != null) && !rangeOp.isEmpty());
addJoinKey(
joinKeys.get(rightInput),
rightKey,
(rangeOp != null) && !rangeOp.isEmpty());
if (filterNulls != null
&& kind == SqlKind.EQUALS) {
// nulls are considered not matching for equality comparison
// add the position of the most recently inserted key
filterNulls.add(joinKeys.get(leftInput).size() - 1);
}
if (rangeOp != null
&& kind != SqlKind.EQUALS
&& kind != SqlKind.IS_DISTINCT_FROM) {
SqlOperator op = call.getOperator();
if (reverse) {
op = requireNonNull(op.reverse());
}
rangeOp.add(op);
}
return;
} // else fall through and add this condition as nonEqui condition
}
// The operator is not of RexCall type
// So we fail. Fall through.
// Add this condition to the list of non-equi-join conditions.
nonEquiList.add(condition);
}