/** Creates a call to a windowed agg. */
public RexNode makeOver(
RelDataType type,
SqlAggFunction operator,
List<RexNode> exprs,
List<RexNode> partitionKeys,
ImmutableList<RexFieldCollation> orderKeys,
RexWindowBound lowerBound,
RexWindowBound upperBound,
boolean physical,
boolean allowPartial,
boolean nullWhenCountZero) {
assert operator != null;
assert exprs != null;
assert partitionKeys != null;
assert orderKeys != null;
final RexWindow window = makeWindow(partitionKeys, orderKeys, lowerBound, upperBound, physical);
final RexOver over = new RexOver(type, operator, exprs, window);
RexNode result = over;
// This should be correct but need time to go over test results.
// Also want to look at combing with section below.
if (nullWhenCountZero) {
final RelDataType bigintType = getTypeFactory().createSqlType(SqlTypeName.BIGINT);
result =
makeCall(
SqlStdOperatorTable.CASE,
makeCall(
SqlStdOperatorTable.GREATER_THAN,
new RexOver(bigintType, SqlStdOperatorTable.COUNT, exprs, window),
makeLiteral(BigDecimal.ZERO, bigintType, SqlTypeName.DECIMAL)),
ensureType(
type, // SUM0 is non-nullable, thus need a cast
new RexOver(
typeFactory.createTypeWithNullability(type, false), operator, exprs, window),
false),
makeCast(type, constantNull()));
}
if (!allowPartial) {
Util.permAssert(physical, "DISALLOW PARTIAL over RANGE");
final RelDataType bigintType = getTypeFactory().createSqlType(SqlTypeName.BIGINT);
// todo: read bound
result =
makeCall(
SqlStdOperatorTable.CASE,
makeCall(
SqlStdOperatorTable.GREATER_THAN_OR_EQUAL,
new RexOver(
bigintType, SqlStdOperatorTable.COUNT, ImmutableList.<RexNode>of(), window),
makeLiteral(BigDecimal.valueOf(2), bigintType, SqlTypeName.DECIMAL)),
result,
constantNull);
}
return result;
}
