Re: Add quto increment to existing column

Robert --

>Hi,
>
>
>I have a column in a table called hist_id with the datatype "integer". When I created the table I assigned this column the primary key constraint but didn´t make it an auto-increment column.
>
>
>How could I do this to an the already existing column?
>
>
>I have created the sequence with the following command but don´t know how to change the existing column to auto-increment.
>
>
>
>
>$ create sequence hist_id_seq;
>

Perhaps:

ALTER TABLE history_foo ALTER COLUMN hist_id SET DEFAULT nextval('hist_id_seq');

?? (untested)

You may need to to update the sequence to reflect your current highest value for hist_id (or whatever the column is -- set the sequence using select setval('hist_id_seq', maxid)  so that the next value you get from the sequence doesn't collide with existing values.

HTH,

Greg Williamson