DROP CONVERSION SQL - Language Statements DROP CONVERSION remove a user-defined conversion DROP CONVERSION conversion_name [ CASCADE | RESTRICT ] DROP CONVERSION removes a previously defined conversion. To be able to drop a conversion, you must own the conversion. conversion_name The name of the conversion. The conversion name may be schema-qualified. CASCADE RESTRICT These key words do not have any effect, since there are no dependencies on conversions. To drop the conversion named myname: DROP CONVERSION myname; There is no DROP CONVERSION statement in the SQL standard.