Re: Query Planner GROUP BY and HAVING clauses optimization ?
Simon Slavin <[email protected]>
| Newsgroups | gmane.comp.db.sqlite.general |
|---|---|
| Message-ID | <[email protected]> |
On 14 Jan 2020, at 4:14pm, Jean-Baptiste Gardette <[email protected]> wrote: > The reason i asked this is that i have a query in wich one condition filtering the recordset involves > an UDF and this UDF needs to be processed after all table filters have been applied You cannot guarantee this. And even if you find a solution that works now, the optimizer in a future version of SQLite might work differently. Would it be possible to phrase your SELECT as a SELECT with a sub-SELECT ? Have the sub-SELECT figure out which rows you want in which order, then use a SELECT to apply your UDF to them ? It is guaranteed that the sub-SELECT is processed before the SELECT. _______________________________________________ sqlite-users mailing list [email protected] http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users