my-ship-it opened a new issue, #1234:
URL: https://github.com/apache/cloudberry/issues/1234
Currently, runtime filter only support Seqscan and Dynamic Seqscan, which
has a positive performance gain for HashJoin, because it reduces probe
HashTable cost when doing join by bloom filter.
For example,
```
postgres=# EXPLAIN (ANALYZE, COSTS OFF, SUMMARY OFF, TIMING OFF)
SELECT t1.c3 FROM t1, t2 WHERE t1.c2 = t2.c2;
QUERY PLAN
-------------------------------------------------------------------------------------------
Gather Motion 3:1 (slice1; segments: 3) (actual rows=0 loops=1)
-> Hash Join (actual rows=0 loops=1)
Hash Cond: (t1.c2 = t2.c2)
Extra Text: (seg2) Hash chain length 8.0 avg, 8 max, using 4 of
524288 buckets.
-> Seq Scan on t1 (actual rows=1 loops=1)
Rows Removed by Pushdown Runtime Filter: 127
-> Hash (actual rows=32 loops=1)
Buckets: 524288 Batches: 1 Memory Usage: 4098kB
-> Seq Scan on t2 (actual rows=32 loops=1)
Optimizer: Postgres query optimizer
(10 rows)
```
For HashJoin, the scan could be FunctionScan, SubqueryScan, TidScan and etc,
so should we support these Scan types, shall we have performance gain?
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