Re: execute many for each commit - Mailing list pgsql-novice

From Tom Lane
Subject Re: execute many for each commit
Date
Msg-id 6801.1329520587@sss.pgh.pa.us
Whole thread Raw
In response to execute many for each commit  (Alessandro Gagliardi <alessandro@path.com>)
List pgsql-novice
Alessandro Gagliardi <alessandro@path.com> writes:
> This is really more of a psycopg2 than a PostgreSQL question per se, but
> hopefully there are a few Pythonistas on this list who can help me out. At
> a recent PUG meeting I was admonished on the folly of committing after
> every execute statement (especially when I'm executing hundreds of inserts
> per second). I was thinking of batching a bunch of execute statements (say,
> 1000) before running a commit but the problem is that if any one of those
> inserts fail (say, because of a unique_violation, which happens quite
> frequently) then I have to rollback the whole batch. Then I'd have to come
> up with some logic to retry each one individually or something similarly
> complicated.

Subtransactions (savepoints) are considerably cheaper than full
transactions.  Alternatively you could consider turning off
synchronous_commit, if you don't need a guarantee that COMMIT means "it's
already safely on disk".

            regards, tom lane

pgsql-novice by date:

Previous
From: Alessandro Gagliardi
Date:
Subject: Foreign Key to an (abstract?) Parent Table
Next
From: Ganesh Borse
Date:
Subject: Request for help on selecting bytea columns using ODBC (windows) from Postgresql DB