[CALCITE-1478] SqlDatetimeSubtractionOperator unparse error

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Not A Problem
• Affects Version/s: 1.11.0
• Fix Version/s: 1.11.0
• Component/s: core
• Assignee: Julian Hyde
• Reporter: Dongming Liu
• Created: 31/Oct/16 05:34
• Updated: 06/Jan/17 19:32
• Resolved: 03/Jan/17 17:55

Description

The expression date '1998-12-01' - interval '108' day(3) parse to SqlNode its operator is SqlMonotonicBinaryOperator, when convert it to RelNode, its operator is SqlDatetimeSubtractionOperator. When I use RelToSqlConverter to convert the RelNode to SqlNode, its operator is also SqlDatetimeSubtractionOperator. Now, sqlNode.toSqlString(sqlDialect).getSql() has a IndexOutOfBoundsException. The source code as follows:

 final SqlWriter.Frame frame = writer.startList("(", ")");
    call.operand(0).unparse(writer, leftPrec, rightPrec);
    writer.sep("-");
    call.operand(1).unparse(writer, leftPrec, rightPrec);
    writer.endList(frame);
    call.operand(2).unparse(writer, leftPrec, rightPrec);

SqlDatetimeSubtractionOperator must have three operands, now it only has two operands.

The following code convert SqlMonotonicBinaryOperator to SqlDatetimeSubtractionOperator,

registerOp(SqlStdOperatorTable.MINUS,
        new SqlRexConvertlet() {
          public RexNode convertCall(SqlRexContext cx, SqlCall call) {
            final RexCall e =
                (RexCall) StandardConvertletTable.this.convertCall(cx, call,
                    call.getOperator());
            switch (e.getOperands().get(0).getType().getSqlTypeName()) {
            case DATE:
            case TIME:
            case TIMESTAMP:
                return convertDatetimeMinus(cx, SqlStdOperatorTable.MINUS_DATE, call);
            default:
              return e;
            }
          }
        });

For date '1998-12-01' - interval '108' day(3), this converter is OK? It only has two operands.