On Friday 24 January 2003 07:37, Andre Schubert wrote: > i have a little question on changing the length of a varchar field. > Is there another way than dump and reload if i want to change the length > of a varchar field ?
in 7.3: BEGIN; ALTER TABLE foo RENAME your_field TO your_field_old; ALTER TABLE foo ADD COLUMN your_field VARCHAR([new length]); UPDATE foo SET your_field=your_field_old; ALTER TABLE foo DROP COLUMN your_field_old; COMMIT; In 7.3, if the new column is shorter you may need to truncate the values being inserted. In versions < 7.3 you will not be able to drop the old column; there you may want to recreate the table, there's a techdoc article here: http://techdocs.postgresql.org/techdocs/updatingcolumns.php > I have search the idocs and found some docs about the system-table > pg_attribute, where the length of a varchar-field is stored in atttypmod. > Is it possible to change the value of atttypmod and is it safe to change > this value? Possible but probably not safe. No doubt someone will be along shortly with a more accurate opinion ;-). Ian Barwick [EMAIL PROTECTED] ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
