[FLINK-19926] Wrong results for join post tumble grouping

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Invalid
• Affects Version/s: 1.11.1
• Component/s: Table SQL / Runtime
• Labels: auto-deprioritized-major

Environment

Flink version: 1.11.1

• Assignee: Unassigned
• Reporter: Satyam Shekhar
• Created: 02/Nov/20 10:38
• Updated: 16/Jun/21 08:00
• Resolved: 16/Jun/21 08:00

Description

I have a table T0 with the following schema -

root
  |-- amount: BIGINT
  |-- timestamp: TIMESTAMP(3)

 

The table T0 has two rows -

amount	timestamp
0	0
1	86400000

 

The following query with tumble grouping returns the wrong result -

WITH CTE AS 
    (SELECT SUM(amount) AS _output, 
                   TUMBLE_END(`timestamp`, INTERVAL '1' SECOND) AS _dim0
           FROM T0 GROUP BY TUMBLE(`timestamp`, INTERVAL '1' SECOND))
SELECT V0._output as V0_output, V1._output AS V1_output, 
               V0._dim0 as V0_time, V1._dim0 as V1_time
    FROM CTE as V0 INNER JOIN CTE V1 ON V0._dim0 = V1._dim0

 
The returned result is -

V0_output	V1_output	V0_time	V1_time
1	1	86401000	86401000

 

The expected result is -

V0_output	V1_output	V0_time	V1_time
0	0	1000	1000
1	1	86401000	86401000

 

Running subquery for `CTE` returns the correct result -

SELECT SUM(amount) AS _output,
              TUMBLE_END(`timestamp`, INTERVAL '1' SECOND) AS _dim0
   FROM T0 GROUP BY TUMBLE(`timestamp`, INTERVAL '1' SECOND)

 

Result (this is correct) -

_output	_dim0
0	1000
1	86401000