Re: Limit vs setMaxRows issue
От | Oliver Jowett |
---|---|
Тема | Re: Limit vs setMaxRows issue |
Дата | |
Msg-id | 4499CDB3.7040007@opencloud.com обсуждение исходный текст |
Ответ на | Limit vs setMaxRows issue (Sebastiaan van Erk <sebster@sebster.com>) |
Ответы |
Re: Limit vs setMaxRows issue
|
Список | pgsql-jdbc |
Sebastiaan van Erk wrote: > Therefore, my question is: is this a bug? It is not feasable for me to > add LIMIT clauses to all the SQL queries in my code, so if this IS a > bug, I hope it can be fixed. If it is NOT a bug, is there an alternative > workaround that does not involve changing all of my sql statements? It's not a bug. setMaxRows() is essentially a hint, there's certainly no requirement that the driver will go off and add LIMIT clauses to your query, the minimal implementation won't change query execution at all and will just limit rows coming back out of the ResultSet.. It might be nice to add LIMIT but that would require the driver to parse query strings which gets very complicated and isn't going to catch all the cases anyway. You'll be getting at least some improvement with the existing driver because the whole resultset isn't being transferred and processed, even if the plan is still assuming you will grab all the data. If your queries need a LIMIT clause to get decent performance then your safest bet is to add a LIMIT clause yourself. You can keep the setMaxRows() as well if you like.. -O
В списке pgsql-jdbc по дате отправления: