Partial join

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Hello,


I attached one example of a partitioned table with multi column partition key. I also attached the output.

Disabling the hash_join is not really necessary, it just shows the more drastic result in the case of low work_mem.


Comparing the first and the second query I was surprised to see that SET enable_partitionwise_join could cause the costs to go up. Shouldn't the paths of the first query be generated as well?



The third query seems to have a different issue. That one is close to my original performance problem. It looks to me like the push down of the sl condition stops the optimizer considering a partial join.

If so would it be sane to keep a copy of the original quals to make the partial join possible?


Regards

Arne

Attachment: querys.sql
Description: querys.sql

Attachment: explain_analyze.sql
Description: explain_analyze.sql


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