Cursors WITH HOLD

Informix®

Informix closes opened cursors automatically when a transaction ends, unless the WITH HOLD option is used in the DECLARE instruction:

DECLARE c1 CURSOR WITH HOLD FOR SELECT ...
OPEN c1
BEGIN WORK
FETCH c1 ...
COMMIT WORK
FETCH c1 ...
CLOSE c1

Oracle® MySQL and MariaDB

With MySQL and MariaDB, opened cursors using SELECT statements without a FOR UPDATE clause are not closed when a transaction ends. All database cursors are WITH HOLD cursors, unless the FOR UPDATE clause is used in the SELECT statement.

Cursors declared FOR UPDATE and using the WITH HOLD option cannot be supported with MySQL because FOR UPDATE cursors are automatically closed by the database server when the transaction ends.

Solution

BDL cursors declared WITH HOLD remain open even after terminating a transaction with a COMMIT WORK or ROLLBACK WORK.

For consistency with other database brands, database cursors that are not declared WITH HOLD are automatically closed, when a COMMIT WORK or ROLLBACK WORK is performed.

Important:

Opening a WITH HOLD cursor declared with a SELECT FOR UPDATE results in an SQL error; in the same conditions, this does not normally appear with Informix. Review the program logic in order to find another way to set locks.