> Hi,
>
> Is it possible to configure postgres from SQL?
>
> I am interested in turning off fsync for a set of queries (that take
> ages to run) and then turn fsync back on again afterwards.
There are things that can be changed at runtime using SQL - in that case
you may just type "SET enable_seqscan = Off" etc.
But you can't change fsync, it does not make sense to change this settings
for individual queries.
As Thom Brown already pointed out, it's not a good way to tune your
queries. If you don't need to keep consistency (which is the purpose of
fsync), then you may change this directly in postgresql.conf. And if you
don't need consistency you must not change that.
Tomas