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 Context VariablesSecurity 

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]

ROLLBACK TO SAVEPOINT

The ROLLBACK TO SAVEPOINT statement specifies the name of a savepoint to which changes are to be rolled back.The effect is to roll back all changes made within the transaction, from the specified savepoint forward until the point when ROLLBACK TO SAVEPOINT is requested.

ROLLBACK TO SAVEPOINT performs the following operations:

  • Any database mutations performed since the savepoint was created are undone.User variables set with RDB$SET_CONTEXT() remain unchanged.

  • Any savepoints that were created after the one named are destroyed.Savepoints earlier than the one named are preserved, along with the named savepoint itself.Repeated rollbacks to the same savepoint are thus allowed.

  • All implicit and explicit record locks that were acquired since the savepoint are released.Other transactions that have requested access to rows locked after the savepoint are not notified and will continue to wait until the transaction is committed or rolled back.Other transactions that have not already requested the rows can request and access the unlocked rows immediately.

See also

[fblangref50-transacs-savepoint], [fblangref50-transacs-releasesp]