Re: simple query question: return latest
От | Scott Frankel |
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Тема | Re: simple query question: return latest |
Дата | |
Msg-id | A87283D8-3450-11D9-B6EE-000A95A7B782@pacbell.net обсуждение исходный текст |
Ответ на | Re: simple query question: return latest (Michael Glaesemann <grzm@myrealbox.com>) |
Ответы |
Re: simple query question: return latest
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Список | pgsql-general |
On Nov 11, 2004, at 5:09 PM, Michael Glaesemann wrote: > Scott, > > On Nov 12, 2004, at 10:00 AM, Scott Frankel wrote: > >> color | date >> --------+------------ >> red | 2004-01-19 >> blue | 2004-05-24 >> red | 2004-04-12 >> blue | 2004-05-24 >> >> >> How do I select the most recent entry for 'red'? >> > > SELECT color, MAX(date) > FROM giventable > WHERE color = 'red' -- omit this line if you'd like to see the latest > date for each color > GROUP BY color; Unless I'm missing something, this returns every listing for color=red, in max order. So if I want the ONE most recent entry, is this something I have to offload to my app that parses the returned rows? Or is there a function in postgres that can return THE most recent entry? > > OT hint: You might want to take a look at the list of PostgreSQL > Keywords in the documentation and avoid using them (such as date) to > help you avoid naming issues in the future. Hmm. Good tip. Bad example terminology. Thanks! Scott > > Hope this helps. > > Michael Glaesemann > grzm myrealbox com > > > ---------------------------(end of > broadcast)--------------------------- > TIP 2: you can get off all lists at once with the unregister command > (send "unregister YourEmailAddressHere" to majordomo@postgresql.org) >
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