Re: Identity and Sequence

On Fri, Feb 16, 2024 at 10:24 AM Michael Corey <michael.corey.ap@nielsen.com> wrote:

By explicitly making a column an IDENTITY column it is going to make a sequence behind the scenes even if one with a similar name exists.  I tried and it created part_tab_part_id_seq1.  Is there no way to have it use the original part_tab_part_id_seq?

No, the fact that there is even a sequence is mostly an implementation detail you shouldn't be concerned with.

Actually you should be concerned with/aware of this detail for the reason you state below.

 

 How do I get the data and the sequence in sync?  

That would be why the alter table command has a bunch of keywords and values as part of it.  So you can modify the values to be what you need.

From

https://www.postgresql.org/docs/current/sql-altertable.html

"

SET sequence_option
RESTART

These forms alter the sequence that underlies an existing identity column. sequence_option is an option supported by ALTER SEQUENCE such as INCREMENT BY.

"

You need to know how a sequence works and what can be modified.

David J.

-- 
Adrian Klaver
adrian.klaver@aklaver.com