Re: why postgresql over other RDBMS - Mailing list pgsql-general

From PFC
Subject Re: why postgresql over other RDBMS
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Msg-id op.ts9id1ogcigqcu@apollo13
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In response to Re: why postgresql over other RDBMS  (Ron Johnson <ron.l.johnson@cox.net>)
Responses Re: why postgresql over other RDBMS
List pgsql-general
>>>     Will the synchronized seq scan patch be able to do this by issuing
>>> all  the CREATE INDEX commands at the same time from several different
>>> database  connections ?
>>  No, but it could someday.

    Actually I tested, it does it right now, albeit unconsciously (pg doesn't
do anything to synchronize the scans, but if you launch the concurrent
connections at the same time and issue all your "create index" at the same
time, only 1 table scan is needed). Maybe if the tables were bigger, it
would lose sync between the 3 concurrent scans and would end up going
slower. That's why I spoke about the "synchronized scan" patch.

> Or would a "CREATE MANY INDEXES" (where in one statement you specify all
> the indexes on a single table) command be easier to implement?

    You can get the effect right now by using concurrent connections it
seems. Not very practical in a psql script, though...

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