Марсельподскажите, так должно быть, когда Commit или autocommit-действие закрывает курсор ?Да, так должно быть.
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SQL Anywhere® Server - Programming > Using SQL in Applications > Controlling transactions in applications > Cursors and transactionsIn general, a cursor closes when a COMMIT is performed. There are two exceptions to this behavior:

The close_on_endtrans database option is set to Off.

A cursor is opened WITH HOLD, which is the default with Open Client and JDBC.

If either of these two cases is true, the cursor remains open on a COMMIT.

ROLLBACK and cursors
If a transaction rolls back, then cursors close except for those cursors opened WITH HOLD. However, don't rely on the contents of any cursor after a rollback.

The draft ISO SQL3 standard states that on a rollback, all cursors (even those cursors opened WITH HOLD) should close. You can obtain this behavior by setting the ansi_close_cursors_on_rollback option to On.

Savepoints
If a transaction rolls back to a savepoint, and if the ansi_close_cursors_on_rollback option is On, then all cursors (even those cursors opened WITH HOLD) opened after the SAVEPOINT close.

Cursors and isolation levels
You can change the isolation level of a connection during a transaction using the SET OPTION statement to alter the isolation_level option. However, this change does not affect open cursors.