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Firebird 2.1 Language Reference Update

Firebird 2.1 Language Reference Update

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Transaction control statements<br />

• The USING option is also ESQL-only. It limits the databases that the transaction can access to the<br />

ones mentioned here.<br />

• IGNORE LIMBO and LOCK TIMEOUT are not supported in ESQL.<br />

• LOCK TIMEOUT and NO WAIT are mutually exclusive.<br />

• Default option settings are: READ WRITE + WAIT + SNAPSHOT.<br />

IGNORE LIMBO<br />

Available in: DSQL<br />

Added in: 2.0<br />

Description: With this option, records created by limbo transactions are ignored. Transactions are in limbo if<br />

the second stage of a two-phase commit fails.<br />

Note<br />

IGNORE LIMBO surfaces the isc_tpb_ignore_limbo TPB parameter, available in the API since InterBase<br />

times and mainly used by gfix.<br />

LOCK TIMEOUT<br />

Available in: DSQL<br />

Added in: 2.0<br />

Description: This option is only available for WAIT transactions. It takes a non-negative integer as argument,<br />

prescribing the maximum number of seconds that the transaction should wait when a lock conflict occurs. If the<br />

the waiting time has passed and the lock has still not been released, an error is generated.<br />

Note<br />

This is a brand new feature in <strong>Firebird</strong> 2. Its API equivalent is the new isc_tpb_lock_timeout TPB parameter.<br />

NO AUTO UNDO<br />

Available in: DSQL, ESQL<br />

Added in: 2.0<br />

Description: With NO AUTO UNDO, the transaction refrains from keeping the log that is normally used to undo<br />

changes in the event of a rollback. Should the transaction be rolled back after all, other transactions will pick up<br />

the garbage (eventually). This option can be useful for massive insertions that don't need to be rolled back. For<br />

transactions that don't perform any mutations, NO AUTO UNDO makes no difference at all.<br />

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