Re: temp tables versus the global sql area

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От Bruce Momjian
Тема Re: temp tables versus the global sql area
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Msg-id 200112170537.fBH5bqS06826@candle.pha.pa.us
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Ответ на temp tables versus the global sql area  (Terrence Brannon <metaperl@mac.com>)
Список pgsql-sql
> In the Momjian book it is stated:
> 
> Temporary tables are ideal for holding intermediate data used by 
> the current SQL session. For example, suppose you need to do many 
> SELECTs on the result of a complex query. An efficient strategy 
> is to execute the complex query once, then store the result in a 
> temporary table.
> 
> 
> ...However, my question is doesn't postgresql calculate the cost 
> of complex queries and store there result in some sort of global 
> sql area sorted by LRU or cost so that you can simply write 
> complex queries and take care of automatic caching?

Nope.  Sorry.  Those caches would have to be invalidated if someone made
a change to those tables.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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