/**
* Copies outer join data from a source MultiJoinRel to a new set of arrays. Also adjusts the
* conditions to reflect the new position of an input if that input ends up being shifted to the
* right.
*
* @param multiJoinRel the source MultiJoinRel
* @param destConds the array where the join conditions will be copied
* @param destJoinTypes the array where the join types will be copied
* @param destPos starting position in the array where the copying starts
* @param adjustmentAmount if > 0, the amount the RexInputRefs in the join conditions need to be
* adjusted by
* @param srcFields the source fields that the original join conditions are referencing
* @param destFields the destination fields that the new join conditions will be referencing
*/
private void copyOuterJoinInfo(
MultiJoinRel multiJoinRel,
RexNode[] destConds,
JoinRelType[] destJoinTypes,
int destPos,
int adjustmentAmount,
RelDataTypeField[] srcFields,
RelDataTypeField[] destFields) {
RexNode[] srcConds = multiJoinRel.getOuterJoinConditions();
JoinRelType[] srcJoinTypes = multiJoinRel.getJoinTypes();
RexBuilder rexBuilder = multiJoinRel.getCluster().getRexBuilder();
int len = srcConds.length;
System.arraycopy(srcJoinTypes, 0, destJoinTypes, destPos, len);
if (adjustmentAmount == 0) {
System.arraycopy(srcConds, 0, destConds, 0, len);
} else {
int nFields = srcFields.length;
int[] adjustments = new int[nFields];
for (int idx = 0; idx < nFields; idx++) {
adjustments[idx] = adjustmentAmount;
}
for (int i = 0; i < len; i++) {
if (srcConds[i] != null) {
destConds[i + destPos] =
srcConds[i].accept(
new RelOptUtil.RexInputConverter(rexBuilder, srcFields, destFields, adjustments));
}
}
}
}
// implement RelOptRule
public void onMatch(RelOptRuleCall call) {
FilterRel filterRel = call.rel(0);
MultiJoinRel multiJoinRel = call.rel(1);
MultiJoinRel newMultiJoinRel =
new MultiJoinRel(
multiJoinRel.getCluster(),
multiJoinRel.getInputs(),
multiJoinRel.getJoinFilter(),
multiJoinRel.getRowType(),
multiJoinRel.isFullOuterJoin(),
multiJoinRel.getOuterJoinConditions(),
multiJoinRel.getJoinTypes(),
multiJoinRel.getProjFields(),
multiJoinRel.getJoinFieldRefCountsMap(),
filterRel.getCondition());
call.transformTo(newMultiJoinRel);
}