Something like
BEGIN; LOCK table_name; ALTER TABLE table_name RENAME col_a to col_a_old; ALTER TABLE table_name ADD COLUMN col_a text; UPDATE table_name SET col_a=col_a_old; ALTER TABLE table_name DROP COLUMN col_a_old; COMMIT;
If you have any referential integrity on the column, you'll have to mess with that first.
Joe Audette wrote:
Hi,
I have an app that I released with a particular field as varchar 255.
Can someone give me a script example I can use to make an upgrade script to change it to text or at least to larger varchar without losing existing data?
I support 3 different dbs in my app, Postgre is the newest and least familiar to me but I am trying to learn.
Any help much appreciated.
Joe Audette
joe_audette [at] yahoo dotcom http://www.joeaudette.com http://www.mojoportal.com
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