[CALCITE-6129] SqlToRelConverter throws an exception when converting a NULL SqlLiteral

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.36.0
• Fix Version/s: 1.37.0
• Component/s: core
• Assignee: Unassigned
• Reporter: Mihai Budiu
• Created: 23/Nov/23 01:50
• Updated: 06/May/24 22:19
• Resolved: 09/Jan/24 17:03

Description

The problem is in SqlNodeToRexConverterImpl.convertLiteral. This function attempts to handle NULL literals differently from all other literals:

    final RexBuilder rexBuilder = cx.getRexBuilder();
    if (literal.getValue() == null) {
      RelDataType type = cx.getValidator().getValidatedNodeType(literal);
      return rexBuilder.makeNullLiteral(type);
    }

    switch (literal.getTypeName()) {
    ...

However, such a literal does not have a validated data type, so getValidatedNodeType will throw Util.needToImplement.

The solution would be to handle NULL literals like all other literals and create a literal with a NULL type.

Issue Links

• is part of: CALCITE-6192 DEFAULT expression with NULL value throws unexpected exception