PostgreSQL Reference Manual - Volume 1 - SQL Language Reference by The PostgreSQL Global Development Group Paperback (6"x9"), 716 pages ISBN 0954612027 RRP £32.00 ($49.95) Sales of this book support the PostgreSQL project! Get a printed copy>>>

PostgreSQL Reference Manual Volume 1 Buy the book here! >>> learn more

3.5.5 Changing a Column's Default Value

To set a new default for a column, use a command like this:

ALTER TABLE products ALTER COLUMN price SET DEFAULT 7.77;

Note that this doesn't affect any existing rows in the table, it just changes the default for future INSERT commands.

To remove any default value, use

ALTER TABLE products ALTER COLUMN price DROP DEFAULT;

This is effectively the same as setting the default to null. As a consequence, it is not an error to drop a default where one hadn't been defined, because the default is implicitly the null value.