Re: Newbie DBD::Pg question

Hi,

Extraction of large amount of data is not realistic especially with
CGI, then DBI/DBD::Pg  always return all data received from a query
so if you don't want to tired your machine, the better way is to use
cursor in a transaction (or query) or the LIMIT+OFFSET keywords.

Regards

Gilles DAROLD

Mithun Bhattacharya wrote:

> Just started on postgres a few days back and was having a few questions
> about the perl interface to it. According to perldoc DBD::Pg
> ----------------
>        Cursors
>
>        Although PostgreSQL has a cursor concept, it has not been
>        used in the current implementation. Cursors in PostgreSQL
>        can only be used inside a transaction block.  Because only
>        one transaction block at a time is allowed, this would
>        have implied the restriction, not to use any nested SELECT
>        statements. Hence the execute method fetches all data at
>        once into data structures located in the frontend
>        application. This has to be considered when selecting
>        large amounts of data !
> -----------------
> Frankly speaking I am not sure what the Author is saying here. Anybody
> cares to point me in the right direction ??? I do have to extract large
> amount of data but I am not sure whether it affects me or not.
>
> Mithun
>
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