UPDATE/DELETE … WHERE CURRENT OF
Informix®
Informix allows positioned UPDATEs and DELETEs with the "WHERE CURRENT OF cursor" clause, if the cursor has been DECLARED with a SELECT ... FOR UPDATE statement.
PostgreSQL
UPDATE/DELETE ... WHERE CURRENT OF is supported by PostgreSQL with server-side
cursors created by a DECLARE statement.
Solution
With PostgreSQL, UPDATE/DELETE ... WHERE CURRENT OF instructions are executed as
is without translation: Since SELECT FOR UPDATE statements are implemented with a
DECLARE statement to get a server cursor, native positioned update/delete can take
place in PostgreSQL.