Re: 700K Inserts in transaction - Mailing list pgsql-performance

From nik9000@gmail.com
Subject Re: 700K Inserts in transaction
Date
Msg-id B3454B20-7024-43C2-A2E2-265AADBEBD1F@gmail.com
Whole thread Raw
In response to 700K Inserts in transaction  (Asmir Mustafic <goetas@lignano.it>)
List pgsql-performance
Are the duplicates evenly distributed?  You might have started on a big chunk of dupes.

I'd go about this by loading my new data in a new table, removing the dupes, then inserting all the new data into the
oldtable. That way you have more granular information about the process. And you can do the initial load with copy if
youneed it. And you can remove the dupes outside of a transaction.  

Nik

Sent from my iPhone

On Feb 14, 2013, at 5:28 AM, Asmir Mustafic <goetas@lignano.it> wrote:

> Hi everybody!
> I'm new in mailing list, and i have a little question.
>
>
> The tables are:
> postalcodes (place_id, code),  PK(place_id, code) 600K of rws
> places (id, name),  PK(id), INDEX(name) 3M of rows
>
> I've to insert another 600k of rows into postalcodes table, in a single transaction, omitting duplicates.
>
> The insert query is a prepared statement like this:
>
> INSERT INTO postalcodes (place_id, code)
> SELECT places.id, :code
> FROM places
> LEFT JOIN postalcodes (postalcodes.place_id = places.id and postalcodes.code = :code)
> WHERE places.name = :name AND postalcodes.place_id IS NULL
>
> Inserting rows works well (3000 queries per second), but when i reach 30K of executed statements, the insert rate
slowsdown to 500/1000 queries per second). 
>
> Doing a commit every 20K of inserts, the insert rate remain 3000 queries per second.
>
> There is a limit of inserts in a transaction?
>
>
>
>
>
> --
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