Re: Erratically behaving query needs optimization - Mailing list pgsql-performance

Hello,

1/ access scheduler_task_executions 
    by index with device_id = 97
seems ok

2/ 
I don't understand why 
joining
scheduler_task_executions.id=scheduler_operation_executions.task_execution_id
is done using a parallel hash join 
when a nested loop would be better (regarding the number of rows involved)

maybe because index on scheduler_operation_executions.task_execution_id

    "index_task_execution_id_desc" btree (task_execution_id DESC NULLS LAST)

is not usable or bloated or because of DESC NULLS LAST ?


3/ join with results.operation_execution_id
    by index
seems OK

Regards
PAscal



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