From: Milen Kulev <makulev@gmx.net>
To: 'Talha Khan' <talha.amjad@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Pipelined functions in Postgres
Date: Tue, 19 Sep 2006 23:29:07 +0200
Message-ID: <008b01c6dc32$a35c5290$0a00a8c0@trivadis.com> (raw)
In-Reply-To: <f80885fc0609191407p496ac28dy5825698e7b5065d0@mail.gmail.com>
Talha,
do you know how much memory is consumed by the SETOF function ?
What happens with memory consumption of the function if
SELECT ename FROM emp WHERE sal > $1
returns 10 mio rows ?
I suppose that memory for the RECORD structure is immediately reused by the next record.
Regards, Milen
-----Original Message-----
From: Talha Khan [mailto:talha.amjad@gmail.com]
Sent: Tuesday, September 19, 2006 11:08 PM
To: Milen Kulev
Cc: pgsql-performance@postgresql.org
Subject: Re: [PERFORM] Pipelined functions in Postgres
Hi Milen,
Pipelined function is a code that acts like a database table.
Inorder to use this functionality in postgres you would need to write the function like this
CREATE OR REPLACE FUNCTION get_test_data (numeric)
RETURNS SETOF RECORD AS
$$
DECLARE
temp_rec RECORD;
BEGIN
FOR temp_rec IN (SELECT ename FROM emp WHERE sal > $1)
LOOP
RETURN NEXT temp_rec;
END LOOP;
RETURN;
END;
$$ LANGUAGE plpgsql;
now inorder to call this function you would write the code as follows
SELECT * FROM get_test_data(1000) AS t1 (emp_name VARCHAR);
Regards
Talha Amjad
On 9/19/06, Milen Kulev <makulev@gmx.net> wrote:
Hello Lister,
I am curios whether I can emulate the Oracle pipelined functions functionality in PG too (using RETURN NEXT ). For more
information and examples about Oracle pipelined functions see:
http://asktom.oracle.com/pls/ask/f?p=4950:8:8127757633768425921::NO::F4950_P8_DISPLAYID,F4950_P8_CRI...
<http://asktom.oracle.com/pls/ask/f?p=4950:8:8127757633768425921::NO::F4950_P8_DISPLAYID,F4950_P8_CRI...>
I have used pipeline functions in DWH enviromnent with success and would like
To use similar concept in PG too.
Any help, examples , links and shared experiences would be greately appreciated.
Best Regards.
Milen
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To: pgsql-performance@postgresql.org
Cc: makulev@gmx.net, talha.amjad@gmail.com
Subject: Re: Pipelined functions in Postgres
In-Reply-To: <008b01c6dc32$a35c5290$0a00a8c0@trivadis.com>
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