Re: Concurrent read from a partition table. - Mailing list pgsql-general

From Chetan Suttraway
Subject Re: Concurrent read from a partition table.
Date
Msg-id CAPtHcnETm07zHjocabFJ4aZHwyBQWyTXhUE9XNN+N16Z1fvWgQ@mail.gmail.com
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In response to Re: Concurrent read from a partition table.  (hyelluas <helen_yelluas@mcafee.com>)
List pgsql-general


On Tue, Jul 12, 2011 at 11:46 PM, hyelluas <helen_yelluas@mcafee.com> wrote:
Hi Chetan,

I'm not sure how I can create a test case, I'm running queryes on 50g of
data to see this.

My general questions are about locking children when select from a parent, I
have not seen any documentation on it. Does any parameter like 'concurrent
read' exist?  I'm still  new to postgres, came from oracle & mysql.


Thanks.
Helen



I tried with the attached test case and found that both the tables - base as well as child tables are locked in shared mode for select queries.
For details, please check the attached inheritance_locks.txt file.

With "concurrent read" did you mean isolation settings?
Then please refer:
http://www.postgresql.org/docs/9.0/static/sql-set-transaction.html


Regards,
Chetan

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EnterpriseDB Corporation
The Enterprise PostgreSQL Company

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