Re: Join question
| От | Jeffrey Melloy |
|---|---|
| Тема | Re: Join question |
| Дата | |
| Msg-id | D1319B84-D9E3-11D7-8AF9-000393C78AC0@visualdistortion.org обсуждение исходный текст |
| Ответ на | Re: Join question ("Williams, Travis L, NEO" <tlw@att.com>) |
| Список | pgsql-general |
On Friday, August 29, 2003, at 12:36 AM, Williams, Travis L, NEO wrote: > Performace wise would I be better off just doing 2 query's.. i.e. > select > a,b from table1.. then in perl I can check if b is not null and if is > isn't then I do a second query? > > Travis > I would say it depends on the table distribution (% of b that are null, etc). At that point, you're just going to have to experiment, I think, and see what works best for you. My gut says that even including a subselect, it will be faster than checking in perl and issuing another query. But I have no idea, and the proper solution might change drastically based on your data. Jeff
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