From: Tom Lane <tgl@sss.pgh.pa.us>
To: Florian Weimer <fweimer@bfk.de>
Cc: pgsql-sql@postgresql.org
Subject: Re: Transaction-specific global variable
Date: Thu, 03 Feb 2011 11:31:46 -0500
Message-ID: <23728.1296750706@sss.pgh.pa.us> (raw)
In-Reply-To: <82zkqdscuc.fsf@mid.bfk.de>
References: <82zkqdscuc.fsf@mid.bfk.de>
Florian Weimer <fweimer@bfk.de> writes:
> hstore greatly simplifies creating triggers for logging table changes,
> which is great. However, when creating a log record, I would like to
> include information about the party who made this change. We
> generally do not allow direct database access for application code, so
> the PostgreSQL user does not provide sufficient information on its
> own. Instead, I'd like to create a transaction-specific variable
> which stores context information to be included in the log table. I
> suppose I could create a stored procedures in C which provides this
> functionality, but I wonder if there is already something similar I
> could reuse. For instance, I could reuse the application_name
> configuration variable, but this seems a bit gross.
You could abuse the custom-GUC-variable mechanism: just set
custom_variable_classes and then define some variable that doesn't
actually have any underlying loadable module.
regards, tom lane
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To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, fweimer@bfk.de
Subject: Re: Transaction-specific global variable
In-Reply-To: <23728.1296750706@sss.pgh.pa.us>
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