[CALCITE-4413] Duplicate RAND() after pushdown when optimizing

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: core
• Assignee: Jiatao Tao
• Reporter: Jiatao Tao
• Created: 20/Nov/20 07:54
• Updated: 07/Dec/20 19:41

Description

In CsvTest:

SQL: 

select *
from
(
    select empno, rand(1) as ran
    from EMPS
    where gender <> 'M'
) t
where ran > 0.6

 

PLAN: 

EnumerableProject(EMPNO=[$0], RAN=[RAND(1)])
  EnumerableInterpreter
    BindableTableScan(table=[[SALES, EMPS]], filters=[[AND(<>($3, 'M'), >(RAND(1), 0.6:DECIMAL(2, 1)))]])

We can see there are two "RAND(1)" and it changes the semantics.