Re: [PATCH] Fix division by zero (explain.c)
От | Tomas Vondra |
---|---|
Тема | Re: [PATCH] Fix division by zero (explain.c) |
Дата | |
Msg-id | 20200509174440.hvzrifqtu7fhbnkq@development обсуждение исходный текст |
Ответ на | Re: [PATCH] Fix division by zero (explain.c) (Ranier Vilela <ranier.vf@gmail.com>) |
Ответы |
Re: [PATCH] Fix division by zero (explain.c)
|
Список | pgsql-hackers |
On Sat, May 09, 2020 at 06:48:59AM -0300, Ranier Vilela wrote: >Em sáb., 9 de mai. de 2020 às 01:45, Tom Lane <tgl@sss.pgh.pa.us> escreveu: > >> James Coleman <jtc331@gmail.com> writes: >> > There are always full sort groups before any prefix groups can happen, >> > so we know (even though the tooling doesn't) that the 2nd test can >> > never contradict the first. >> >> So maybe an assertion enforcing that would be appropriate? >> Untested, but: >> >> - if (fullsortGroupInfo->groupCount == 0 && >> - prefixsortGroupInfo->groupCount == 0) >> + if (fullsortGroupInfo->groupCount == 0) >> + { >> + Assert(prefixsortGroupInfo->groupCount == >> 0); >> continue; >> + } >> >I agree, asserts always help. > That doesn't work, because the prefixSortGroupInfo is used before assignment, producing compile-time warnings. I've pushed a simpler fix without the assert. If we want to make this check, perhaps doing it in incremental sort itself would be better than doing it in explain. regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
В списке pgsql-hackers по дате отправления: