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ROLLBACK WORK
The ROLLBACK WORK statement undoes changes you have made to the
DBEnvironment during the current transaction, releases locks held by the
transaction, and closes cursors opened during the transaction. Other
transactions active in this session are not affected.
Scope
ISQL or Application Programs
SQL Syntax
[ {SavePointNumber }]
[TO {:HostVariable }]
ROLLBACK WORK [ {:LocalVariable }]
[ {:ProcedureParameter}]
[ ]
[RELEASE ]
Parameters
TO The TO clause is used to roll back to a savepoint
without ending the current transaction.
If the TO clause is omitted, ROLLBACK WORK ends
the current transaction and undoes any changes
that have been made in the transaction.
SavePointNumber is the number assigned by ISQL to a savepoint
when you issue the SAVEPOINT statement
interactively.
HostVariable is defined as an integer variable to which you
assign a value when you issue the SAVEPOINT
statement programmatically, or in a procedure.
LocalVariable contains a value in a procedure.
ProcedureParameter contains a value that is passed into or out of a
procedure.
RELEASE terminates your DBE session.
Description
* When you omit the TO clause, all changes you have made to the
DBEnvironment since the most recent BEGIN WORK statement are
undone. In an application program, all open cursors are
automatically closed except those opened with the KEEP CURSOR
option. Any savepoints defined in the transaction are lost and
become invalid. The transaction is ended. Any cursor opened with
the KEEP CURSOR option is repositioned to its scan position as of
the most recent BEGIN WORK statement, and a new transaction is
implicitly started with the same isolation level.
* The TO clause may not be used if any cursors that were opened with
the KEEP CURSOR option are still open. Issuing a ROLLBACK WORK to
a savepoint in this context results in an error message, and no
rollback is done.
* When you specify the TO clause, all changes you have made to the
DBEnvironment since the designated savepoint are undone. If any
cursors opened with the KEEP CURSOR option were active in this
transaction, the statement fails and the rollback is not done. In
an application program or procedure, all open cursors are
automatically closed.
Any savepoints defined more recently than the designated savepoint
are lost and become invalid. The designated savepoint is still
valid and can be specified in a future ROLLBACK WORK statement.
The transaction is not ended. Any locks obtained since the
savepoint was set are released.
* If the current transaction is the one in which you opened a cursor
with the KEEP CURSOR option, then the ROLLBACK WORK statement
closes the cursor and undoes any changes made through it.
* Under some circumstances ALLBASE/SQL automatically rolls back a
transaction. For example, when service is restored after a system
failure, all uncommitted transactions are automatically backed
out.
* If RELEASE is used, all cursors are closed and the current
connection is terminated.
* The RELEASE option is not allowed within a procedure.
Authorization
You do not need authorization to use the ROLLBACK WORK statement.
Example
Transaction begins.
BEGIN WORK
statement-1
SAVEPOINT :MyVariable
statement-2
statement-3
Work of statements 2 and 3 is undone.
ROLLBACK WORK TO :MyVariable
Work of statement 1 is committed; transaction ends.
COMMIT WORK