update strategy

[mrot]

>If you're caching rows, key them in cache by table name and primary key,
>e.g. 'users:13'. Trying to do it by storing queries is usually a bad
>idea for a number of reasons (though it has its purposes), one of which
>you've encountered, and another of which is that there exists an
>infinite number of SQL queries that will return the same row, so you can
>be storing tons of duplicate rows in cache at the same time for no good
>reason.
>  
>

Thanks.
Thanks make sense.
Additionally queries can be long some many space my be taken...

Regards