Removes a sequence.
DROP SEQUENCE [IF EXISTS] <name> [, ...] [CASCADE | RESTRICT]
DROP SEQUENCE removes a sequence generator table. You must own the sequence to drop it (or be a superuser).
Remove the sequence
DROP SEQUENCE myserial;
DROP SEQUENCE is fully conforming with the SQL standard, except that the standard only allows one sequence to be dropped per command. Also, the
IF EXISTS option is a HAWQ extension.