Re: Replication Syatem

"Pavan Deolasee" <pavan(dot)deolasee(at)gmail(dot)com> writes:

>> Any special guideline to follow to make HOT working??
>>
>
> You can do couple of things to benefit from HOT.
>
> 1. HOT addresses a special, but common case where UPDATE operation
> does not change any of the index keys. So check if your UPDATE changes
> any of the index keys. If so, see if you can avoid having index
> involving that column. Of course, I won't advocate dropping an index
> if it would drastically impact your frequently run queries.
>
> 2. You may leave some free space in the heap (fillfactor less than
> 100). My recommendation would be to leave space worth of one row or
> slightly more than that to let first UPDATE be an HOT update.
> Subsequent UPDATEs in the page may reuse the dead row created by
> earlier UPDATEs.
>
> 3. Avoid any long running transactions.

Perhaps we should put this list in the FAQ.

--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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