Re: Best way to get the latest revision from a table

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От Shaun Thomas
Тема Re: Best way to get the latest revision from a table
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Msg-id D247E79EFD801E40A9449A9724F6295B4C5F5F4E@spswchi6mail1.peak6.net
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Ответ на Re: Best way to get the latest revision from a table  (Tom Lane <tgl@sss.pgh.pa.us>)
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> Shaun's example is a bit off: normally, when using DISTINCT ON, you want
> an ORDER BY key that uses all the given DISTINCT keys and then some
> more.  To get the max revision for each a/b combination it ought to be

Hah, well i figured I was doing something wrong. I just thought about it a little bit, said to myself: "Hey, I've used
thisbefore to get the most recent x for a bunch of y without a sub-query. We always used it to get the newest update to
anevent log. 

But that's why I said I was probably misunderstanding something. :) I was trying to pick apart the logic to his temp
tablesand saw the max(b) and it threw me off. Glad you're around to set it straight. Heh. 


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