public static RexNode projectNonColumnEquiConditions(ProjectFactory factory, RelNode[] inputRels,
List<RexNode> leftJoinKeys, List<RexNode> rightJoinKeys, int systemColCount,
List<Integer> leftKeys, List<Integer> rightKeys) {
RelNode leftRel = inputRels[0];
RelNode rightRel = inputRels[1];
RexBuilder rexBuilder = leftRel.getCluster().getRexBuilder();
RexNode outJoinCond = null;
int origLeftInputSize = leftRel.getRowType().getFieldCount();
int origRightInputSize = rightRel.getRowType().getFieldCount();
List<RexNode> newLeftFields = new ArrayList<RexNode>();
List<String> newLeftFieldNames = new ArrayList<String>();
List<RexNode> newRightFields = new ArrayList<RexNode>();
List<String> newRightFieldNames = new ArrayList<String>();
int leftKeyCount = leftJoinKeys.size();
int i;
for (i = 0; i < origLeftInputSize; i++) {
final RelDataTypeField field = leftRel.getRowType().getFieldList().get(i);
newLeftFields.add(rexBuilder.makeInputRef(field.getType(), i));
newLeftFieldNames.add(field.getName());
}
for (i = 0; i < origRightInputSize; i++) {
final RelDataTypeField field = rightRel.getRowType().getFieldList().get(i);
newRightFields.add(rexBuilder.makeInputRef(field.getType(), i));
newRightFieldNames.add(field.getName());
}
int newKeyCount = 0;
List<Pair<Integer, Integer>> origColEqConds = new ArrayList<Pair<Integer, Integer>>();
for (i = 0; i < leftKeyCount; i++) {
RexNode leftKey = leftJoinKeys.get(i);
RexNode rightKey = rightJoinKeys.get(i);
if (leftKey instanceof RexInputRef && rightKey instanceof RexInputRef) {
origColEqConds.add(Pair.of(((RexInputRef) leftKey).getIndex(),
((RexInputRef) rightKey).getIndex()));
} else {
newLeftFields.add(leftKey);
newLeftFieldNames.add(null);
newRightFields.add(rightKey);
newRightFieldNames.add(null);
newKeyCount++;
}
}
for (i = 0; i < origColEqConds.size(); i++) {
Pair<Integer, Integer> p = origColEqConds.get(i);
RexNode leftKey = leftJoinKeys.get(i);
RexNode rightKey = rightJoinKeys.get(i);
leftKeys.add(p.left);
rightKeys.add(p.right);
RexNode cond = rexBuilder.makeCall(
SqlStdOperatorTable.EQUALS,
rexBuilder.makeInputRef(leftKey.getType(), systemColCount + p.left),
rexBuilder.makeInputRef(rightKey.getType(), systemColCount + origLeftInputSize
+ newKeyCount + p.right));
if (outJoinCond == null) {
outJoinCond = cond;
} else {
outJoinCond = rexBuilder.makeCall(SqlStdOperatorTable.AND, outJoinCond, cond);
}
}
if (newKeyCount == 0) {
return outJoinCond;
}
int newLeftOffset = systemColCount + origLeftInputSize;
int newRightOffset = systemColCount + origLeftInputSize + origRightInputSize + newKeyCount;
for (i = 0; i < newKeyCount; i++) {
leftKeys.add(origLeftInputSize + i);
rightKeys.add(origRightInputSize + i);
RexNode cond = rexBuilder.makeCall(SqlStdOperatorTable.EQUALS,
rexBuilder.makeInputRef(newLeftFields.get(i).getType(), newLeftOffset + i),
rexBuilder.makeInputRef(newLeftFields.get(i).getType(), newRightOffset + i));
if (outJoinCond == null) {
outJoinCond = cond;
} else {
outJoinCond = rexBuilder.makeCall(SqlStdOperatorTable.AND, outJoinCond, cond);
}
}
// added project if need to produce new keys than the original input
// fields