From: Jim Buttafuoco <jim@contactbda.com>
To: pw <p.willis@telus.net>
To: pgsql-interfaces@postgresql.org
Subject: Re: Question about accessing current row data inside trigger
Date: Tue, 8 Mar 2005 18:27:06 -0500
Message-ID: <20050308232604.M14503@contactbda.com> (raw)
In-Reply-To: <422E2DD4.1070509@telus.net>
References: <422E2DD4.1070509@telus.net>
have you looked in the contrib directory (Postgresql 7.4.6). I just checked and the dbmirror/pending.c looks like
some good code to follow.
Jim
---------- Original Message -----------
From: pw <p.willis@telus.net>
To: pgsql-interfaces@postgresql.org
Sent: Tue, 08 Mar 2005 14:57:24 -0800
Subject: [INTERFACES] Question about accessing current row data inside trigger
> *previously posted this to pgsql-general*
>
> -Hello,
> -
> -I have a trigger function written in C.
> -The trigger function is called via:
> -
> -CREATE TRIGGER after_update AFTER UPDATE ON some_table
> - FOR EACH ROW EXECUTE PROCEDURE my_trigger_function();
> -
> - Since the trigger is called after each row update the actual
> -row data
> -should be available in some way to the trigger.
> -
> - What functionality (SPI ?) do I use to use the column values -from the
> -current row in the actual trigger?
> -
> - Does SPI_cursor_fetch automatically give me the current trigger -row or
> -do I need to query again for the proper row?
> -
> -thanks for any insight,
> -
> -Peter
>
> I am now using :
>
> TupleTableSlot *t = (TupleTableSlot *) PG_GETARG_POINTER(0);
> bool isnull;
>
> char *buffer=(char *)DatumGetPointer(GetAttributeByName(t,
> "some_column_name", &isnull));
>
> The pointer always comes back NULL though there is data
> in the column.
>
> I'm still not sure this is the correct way to access
> the data from the updated row.
>
> Is this the correct way to get a string back from
> the data in the column named 'some_column_name'?
>
> Do I have the correct TupleTableSlot pointer?
>
> Thanks for any insight,
>
> Peter
>
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------- End of Original Message -------
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To: pgsql-interfaces@postgresql.org
Cc: jim@contactbda.com, p.willis@telus.net
Subject: Re: Question about accessing current row data inside trigger
In-Reply-To: <20050308232604.M14503@contactbda.com>
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