Re: [GENERAL] Whether the function exists a in pgsql table or not?

2011-08-30 Thread shuaixf
My friend, thanks for your replay, however how to prove your view?

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Re: [GENERAL] Whether the function exists a in pgsql table or not?

2011-08-28 Thread Greg Smith

On 08/27/2011 01:21 PM, shuaixf wrote:

In Oracle, when the table has few records, used frequently, it would use
"storage(buffer_pool keep)" to keep the data in cache instead of LRU
algorithm.

if the function exists in a pgsql table or not?
   


There aren't any controls to pin a table into memory in PostgreSQL.  The 
way the database uses both its dedicated buffer cache as well as the OS 
one, it's hard to even define such a UI that would make sense--the 
database doesn't have any control or interaction with the OS cache.


The mechanism for deciding what stays in the PostgreSQL cache is a bit 
more complicated than an LRU, while the one in the OS probably is a 
LRU.  If the table is used frequently, it's very likely to stay in one 
of the two caches anyway.


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Greg Smith   2ndQuadrant USg...@2ndquadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.


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[GENERAL] Whether the function exists a in pgsql table or not?

2011-08-27 Thread shuaixf
In Oracle, when the table has few records, used frequently, it would use
"storage(buffer_pool keep)" to keep the data in cache instead of LRU
algorithm.

if the function exists in a pgsql table or not?


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