From: | Craig Ringer <ringerc(at)ringerc(dot)id(dot)au> |
---|---|
To: | tamanna madaan <tamanna(dot)madaan(at)globallogic(dot)com> |
Cc: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: calling a C function from pgsql function |
Date: | 2012-08-29 13:35:39 |
Message-ID: | 503E1AAB.8060504@ringerc.id.au |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-general |
On 08/29/2012 09:18 PM, tamanna madaan wrote:
> 1. what are the ways to get the value returned by this library function .
You need to wrap the C library function with a PostgreSQL C extension
that uses the fmgr.h APIs, so it's callable from SQL and can return a
result to SQL. See:
http://www.postgresql.org/docs/current/static/xfunc-c.html
> 2. when test1 is called, will it wait for "test1" to return before
> continuing with the next statement in "test" or it will continue with
> the next statement parallely while "test1" is being executed.
The call will return when the C wrapper function returns, so they'll be
executed in series not in parallel.
> 3. Moreover, will test1 be called sequentially in order for all the
> three arguments i.e arg1 first and arg3 in last. Or there can be a
> different order.
The calls will be executed in the order they appear in the PL/PgSQL
function.
--
Craig Ringer
From | Date | Subject | |
---|---|---|---|
Next Message | Pavel Stehule | 2012-08-29 13:37:22 | Re: calling a C function from pgsql function |
Previous Message | Chris Angelico | 2012-08-29 13:33:05 | Re: PQfformat question and retrieving bytea data in C |