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From: Richard Broersma <richard.broersma@gmail.com>
To: "wyx6fox@sina.com" <wyx6fox@sina.com>
In-Reply-To: <20100202045701.93A404B1C73@mail175-236.sinamail.sina.com.cn>
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Subject: Re: the jokes for pg concurrency write performance
Date: Mon, 1 Feb 2010 21:54:07 -0800
Cc: "pgsql-performance@postgresql.org" <pgsql-performance@postgresql.org>

On Feb 1, 2010, at 8:57 PM, wyx6fox@sina.com wrote:

> i found a joke ,maybe this joke concurrency strategy is the  
> designer's pround idea, but i think it is a joke , next let me  
> describe the problems:
>
  I would suggest that the behavior that you dislike so much is really  
not idea of the postgresql developers as much as it is of Prof. Codd  
and the ANSI-SQL committee.  I wonder if a creditable relational DBMS  
exists that doesn't behave in exactly the way you've described?


> UPDATE webpages SET hits = hits + 1 WHERE url ='some url ';
>
>  i say ,u should no kill concurrency performance
>

One alternative design would be to log the timestamp of your web page  
hits rather than update a hits count field.

Once you have this design, if the table becomes volumous with  
historical logs you have the choice the use horizontal table  
partitioning or you can roll up all of the historical logs into an  
aggregating materialized view(table).

Regarding all of the jokes you mentioned, I found them all to be very  
funny indeed.  :)

Regards,
Richard