Adrian Klaver <adrian.klaver@xxxxxxxxxxx> writes: > On 1/16/24 09:45, Jim Vanns wrote: >> I have a slow (CPU bound) DELETE statement I'm attempting to debug and I >> suspect that its actually the ON DELETE CASCADE on the foreign key thats >> causing it. 99% of the time, the cause is lack of an index on the foreign key's referencing columns. We make you have a unique index on the referenced columns, because otherwise the FK constraint's semantics are unclear. But you're not required to make one on the other side. >> What I need is a way to see into this statement as it executes to >> confirm my suspicion - does anyone have any tips on that? > Explain: > https://www.postgresql.org/docs/current/sql-explain.html Specifically, if EXPLAIN ANALYZE shows a lot of time spent in the enforcement trigger for the FK, this is likely what's happening. regards, tom lane
