[CALCITE-4256] RexSimplify should not simplify P AND P to P, if it contains a call to RAND or RAND_INTEGER

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Assignee: Unassigned
• Reporter: Thomas Rebele
• Created: 14/Sep/20 17:35
• Updated: 16/Sep/20 10:39

Description

Example: RAND_INTEGER() = 1 AND RAND_INTEGER() = 1 is false with a higher probability than RAND_INTEGER() = 1

Here a test case for RexProgramTest:

@Test void testSimplifyRandomAnd() {
    checkSimplifyUnchanged(
        and(
            eq(rexBuilder.makeCall(SqlStdOperatorTable.RAND_INTEGER), literal(1)),
            eq(rexBuilder.makeCall(SqlStdOperatorTable.RAND_INTEGER), literal(1))
        ));
  }