DROP CONVERSION — remove a conversion
DROP CONVERSION [ IF EXISTS ] name [ CASCADE | RESTRICT ]
DROP CONVERSION removes a previously defined conversion. To be able to drop a conversion, you must own the conversion.
IF EXISTSDo not throw an error if the conversion does not exist. A notice is issued in this case.
nameThe name of the conversion. The conversion name can be schema-qualified.
CASCADERESTRICTThese 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, but a DROP TRANSLATION statement that goes along with the CREATE TRANSLATION statement that is similar to the CREATE CONVERSION statement in PostgreSQL.
Read the upstream documentation. For corrections, first check the current version.