Question

How to drop domain data type in postgresql ?

Answer 1

You can drop domain data type using following command

postgres=# drop domain us_postal_code;
ERROR:  cannot drop type us_postal_code because other objects depend on it
DETAIL:  table us_snail_addy column postal depends on type us_postal_code
HINT:  Use DROP ... CASCADE to drop the dependent objects too.

postgres=# drop domain us_postal_code casecade;
ERROR:  syntax error at or near "casecade"
LINE 1: drop domain us_postal_code casecade;

postgres=# drop domain us_postal_code cascade; 
NOTICE:  drop cascades to table us_snail_addy column postal
DROP DOMAIN