Andreas Kretschmer wrote:
Andreas Kretschmer <akretschmer@xxxxxxxxxxxxx> schrieb:
Adam <adam@xxxxxxxxxxxxxxxxxx> schrieb:
I just emptied my table and I want all my new inserts to start with a
'location_id' of '1'. The table is named "locations" with a SERIAL column
"location_id"
If you want to start at 1 why not
SELECT setval('locations_location_id_seq', 1);
I tried the below SQL to rest the sequence ID but it's not working. What am I
doing wrong?
SELECT setval('locations_location_id_seq', (SELECT max(location_id) + 1 FROM
locations));
The table locations are empty? Yeah, select max(location_id) from an
empty table is NULL, not 0. And NULL+1 -> NULL. You can't set a Sequence
to NULL, that makes no sense.
Btw, to avoid this, you can use coalesce():
SELECT setval('locations_location_id_seq', (SELECT coalesce(max(location_id),0) + 1 FROM locations));
coalesce returns the first non-null value, either the result from max()
or the second parameter, 0.
Andreas
