Re: PostgreSQL clustering VS MySQL clustering

Matt Clark wrote:

> Presumably it can't _ever_ know without being explicitly told, because 
> even for a plain SELECT there might be triggers involved that update 
> tables, or it might be a select of a stored proc, etc.  So in the 
> general case, you can't assume that a select doesn't cause an update, 
> and you can't be sure that the table list in an update is a complete 
> list of the tables that might be updated.

Uhmmm no :) There is no such thing as a select trigger. The closest you 
would get
is a function that is called via select which could be detected by 
making sure
you are prepending with a BEGIN or START Transaction. Thus yes pgPool 
can be made
to do this.

Sincerely,

Joshua D. Drake



>
>
>
> Tatsuo Ishii wrote:
>
>> Can I ask a question?
>>
>> Suppose table A gets updated on the master at time 00:00. Until 00:03
>> pgpool needs to send all queries regarding A to the master only. My
>> question is, how can pgpool know a query is related to A?
>> -- 
>> Tatsuo Ishii
>>
>>  
>>
>
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