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ROLLBACK

Rolls back a transaction or to a savepoint

Available in

DSQL, ESQL

Syntax
  ROLLBACK [TRANSACTION tr_name] [WORK]
    [RETAIN [SNAPSHOT] | RELEASE]
| ROLLBACK [WORK] TO [SAVEPOINT] sp_name
Table 1. ROLLBACK Statement Parameters
Parameter Description

tr_name

Transaction name.Available only in ESQL

sp_name

Savepoint name.Available only in DSQL

The ROLLBACK statement rolls back all work carried out in the context of this transaction (inserts, updates, deletes, selects, execution of procedures).ROLLBACK never fails and, thus, never causes exceptions.Unless the RETAIN clause is employed, all server resources allocated to the work of the transaction are released.

The TRANSACTION and RELEASE clauses are only valid in ESQL.The ROLLBACK TO SAVEPOINT statement is not available in ESQL.

ROLLBACK Options

  • The optional TRANSACTION tr_name clause, available only in Embedded SQL, specifies the name of the transaction to be committed.With no TRANSACTION clause, ROLLBACK is applied to the default transaction.

    Note

    In ESQL applications, named transactions make it possible to have several transactions active simultaneously in one application.If named transactions are used, a host-language variable with the same name must be declared and initialized for each named transaction.This is a limitation that prevents dynamic specification of transaction names and thus, rules out transaction naming in DSQL.

  • The keyword RETAIN keyword specifies that, although all work of the transaction is to be rolled back, the transaction context is to be retained.Some server resources are retained, and the transaction is restarted transparently with the same Transaction ID.The state of row caches and cursors is kept as it was before the “soft” rollback.

    For transactions whose isolation level is SNAPSHOT or SNAPSHOT TABLE STABILITY, the view of database state is not updated by the soft rollback to reflect changes by other transactions.The user of the application instance continues to have the same view as when the transaction started originally.Changes that were made and soft-committed during the life of the retained transaction are visible to that transaction, of course.

See also

[fblangref50-transacs-settransac], [fblangref50-transacs-commit]