Ger Timmens <Ger.Timmens at adyen.com> writes:
> Can we change the definitions of all 'timestamp' columns
> from 'timestamp without time zone' to timestamp with time stamp'
> in slony (we are using 1.2.20 rightnow).

Sure, you could submit DDL requests via the slonik command EXECUTE
SCRIPT
   <http://slony.info/documentation/1.2/stmtddlscript.html>

The script would consist of a series of ALTER TABLE commands, one for
each column to be thus altered.

I suspect you'll find this to be a mighty expensive operation, as it:

  a) locks all the tables (in 1.2, ALL replicated tables, in 2.0, just
     the ones that need to be altered) for the duration, and

  b) fairly likely leads to the affected tables being rewritten, so all
     the old tuples are dead, so they need vacuuming rather badly.

So, expensive, but it can certainly be done.
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