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

Clemens Eisserer <linuxhippy@gmail.com>

From: Clemens Eisserer <linuxhippy@gmail.com>
To: pgsql-general@postgresql.org
Date: 2013-03-26T13:24:56Z
Lists: pgsql-general
Hi Richard,

>>  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.

Thanks for the clarification.

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

Because the "other" database which I would like to keep in sync is a
MySQL db. Furthermore I do not need a 1:1 replica, but instead just
update a few columns in different tables there.

My inital plan was to add a timestamp-column which is updated at every
Update and to poll for changes every 5-10s. However, the word
"polling" seems to cause an allergic reaction for some poeple ;)

Thanks, Clemens