| From: | Michael Lewis <mlewis(at)entrata(dot)com> |
|---|---|
| To: | Robins Tharakan <tharakan(at)gmail(dot)com> |
| Cc: | PostgreSQL General <pgsql-general(at)lists(dot)postgresql(dot)org> |
| Subject: | Re: Apply LIMIT when computation is logically irrelevant |
| Date: | 2020-07-06 19:51:36 |
| Message-ID: | CAHOFxGqETwver1DDy-pcZT3+Z8fw+yyiuLwCC-rNAF1rA9ayqg@mail.gmail.com |
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| Lists: | pgsql-general |
On Mon, Jul 6, 2020 at 5:37 AM Robins Tharakan <tharakan(at)gmail(dot)com> wrote:
> This need came up while reviewing generated SQL, where the need was to
> return true when
> at least one of two lists had a row.
>
Generated SQL... yep. That will happen. Manual SQL may be more work, but
often has significant reward.
If you can change how the SQL is generated, I would expect that EXISTS
would likely be more performant in your case, even if you need to do UNION
ALL between the two current queries that potentially return true.
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