On 2021-Jul-25, Tom Lane wrote: > Perhaps there's no actual bug there, but it's still horrible coding. > For one thing, the implication that found could be negative is extremely > confusing to readers. A boolean might be better. However, I wonder why > you bothered with a flag in the first place. The usual convention if > we know there can be only one match is to just not write a loop at all, > with a suitable comment, like this pre-existing example elsewhere in > trigger.c: > > /* There should be at most one matching tuple */ > if (HeapTupleIsValid(tuple = systable_getnext(tgscan))) > > If you're not quite convinced there can be only one match, then it > still shouldn't be an Assert --- a real test-and-elog would be better.
I agree that coding there was dubious. I've removed the flag and assert. Arne complained that there should be a unique constraint on (tgrelid, tgparentid) which would sidestep the need for this to be a loop. I don't think it's really necessary, and I'm not sure how to create a system index WHERE tgparentid <> 0. -- Álvaro Herrera 39°49'30"S 73°17'W — https://www.EnterpriseDB.com/ "Saca el libro que tu religión considere como el indicado para encontrar la oración que traiga paz a tu alma. Luego rebootea el computador y ve si funciona" (Carlos Duclós)
