2011-10-04 13:30 keltezéssel, Robert Buckley írta:
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;
You also need to add a DEFAULT expression and optionally
make the sequence owned by the column:
ALTER TABLE tablename ALTER COLUMN hist_id SET DEFAULT nextval('hist_id_seq');
ALTER SEQUENCE hist_id_seq OWNED BY tablename.hist_id;
The "ALTER SEQUENCE ... OWNED BY ..." will make the sequence
automatically dropped if this column or table is dropped.
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Zoltán Böszörményi
Cybertec Schönig & Schönig GmbH
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