int rightKeyOrdinal = rightKeys.get(i).intValue();
equijoinList.add(builder.makeCall(
SqlStdOperatorTable.EQUALS,
builder.makeInputRef(leftTypes.get(leftKeyOrdinal).getType(), leftKeyOrdinal),
builder.makeInputRef(rightTypes.get(rightKeyOrdinal).getType(), rightKeyOrdinal + numLeftFields)
) );
}
newJoinCondition = RexUtil.composeConjunction(builder, equijoinList, false);
} else {
// tracer.warning("Non-equijoins are only supported in the presence of an equijoin.");