Re: psql12.3 + jdbc_fdw - return wrong query results by using OR

Hello,

Please find the info for both SQLs (removed yr)

For Q1:

QUERY PLAN
-------------------------------------------------------------------------------------------------------------------------------
Aggregate (cost=5.40..5.41 rows=1 width=8) (actual time=1267.001..1267.001 rows=1 loops=1)
-> Hash Join (cost=2.10..4.78 rows=245 width=0) (actual time=0.134..1265.840 rows=2650 loops=1)
Hash Cond: (a.c1 = b.c1)
-> Foreign Scan on oracle_t1 a (cost=0.00..0.00 rows=1000 width=32) (actual time=0.026..1257.823 rows=14625 loops=1)
-> Hash (cost=1.49..1.49 rows=49 width=5) (actual time=0.030..0.030 rows=49 loops=1)
Buckets: 1024 Batches: 1 Memory Usage: 10kB
-> Seq Scan on local_t1 b (cost=0.00..1.49 rows=49 width=5) (actual time=0.014..0.021 rows=49 loops=1)
Planning Time: 0.178 ms
Execution Time: 1363.482 ms

For Q2:

QUERY PLAN
----------------------------------------------------------------------------------------------------------------------------
Aggregate (cost=737.71..737.72 rows=1 width=8) (actual time=1197.366..1197.366 rows=1 loops=1)
-> Nested Loop (cost=0.00..736.49 rows=489 width=0) (actual time=16.649..1197.292 rows=70 loops=1)
Join Filter: ((a.c1 = b.c1) OR (a.c2 = b.c1))
Rows Removed by Join Filter: 14555
-> Seq Scan on local_t1 b (cost=0.00..1.49 rows=49 width=5) (actual time=0.016..0.023 rows=49 loops=1)
-> Foreign Scan on oracle_t1 a (cost=0.00..0.00 rows=1000 width=64) (actual time=0.002..24.284 rows=298 loops=49)
Planning Time: 0.972 ms
Execution Time: 1299.896 ms

Thanks a lot.