Re: Do "after update" trigger block the current transaction?

Richard Huxton <dev@archonet.com>

From: Richard Huxton <dev@archonet.com>
To: Clemens Eisserer <linuxhippy@gmail.com>
Cc: pgsql-general@postgresql.org
Date: 2013-03-26T11:22:18Z
Lists: pgsql-general
On 26/03/13 08:52, Clemens Eisserer wrote:
> Hi,
>
> We are currently evaluating the feasibility of executing long-running
> scripts written in shell-script (plsh) called by triggers (after
> update/insert) to synchronize two databases. Will triggers (after
> update specifically) cause the execution of SQL-commands to pause
> until the trigger-function has returned (at statement execution time
> or commit)?

The trigger will block. If it didn't then it couldn't abort the 
transaction if it needed to.

> The other possible approach would be to use polling on some
> trigger-updated timestamp-column, which is not pretty but should be
> fairly simple.

Why not use one of the established trigger-based replication solutions?

-- 
   Richard Huxton
   Archonet Ltd