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DbEnv::set_tx_recover
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#include <db_cxx.h>
int
DbEnv::set_tx_recover(int (*)(DbEnv *dbenv,
Dbt *log_rec, DbLsn *lsn, db_recops op));
Description
Set the application's method to be called during transaction abort
and recovery. This method must return 0 on success and either
errno or a value outside of the Berkeley DB error name space on
failure. It takes four arguments:
- dbenv
- A Berkeley DB environment.
- log_rec
- A log record.
- lsn
- A log sequence number.
- op
- One of the following values:
- DB_TXN_BACKWARD_ROLL
- The log is being read backward to determine which transactions have been
committed and to abort those operations that were not; undo the operation
described by the log record.
- DB_TXN_FORWARD_ROLL
- The log is being played forward; redo the operation described by the log
record.
- DB_TXN_ABORT
- The log is being read backward during a transaction abort; undo the
operation described by the log record.
- DB_TXN_APPLY
- The log is being applied on a replica site; redo the operation
described by the log record.
The DB_TXN_FORWARD_ROLL and DB_TXN_APPLY operations
frequently imply the same actions, redoing changes that appear in the
log record. The macro DB_REDO(op) checks that the operation is one of
DB_TXN_FORWARD_ROLL or DB_TXN_APPLY, and should be used
in the recovery code to refer to the conditions under which operations
should be redone. Similarly, the macro DB_UNDO(op) checks if the
operation is one of DB_TXN_BACKWARD_ROLL or DB_TXN_ABORT.
The DbEnv::set_tx_recover interface may be used only to configure Berkeley DB before
the DbEnv::open interface is called.
The DbEnv::set_tx_recover method either returns a non-zero error value or throws an exception that
encapsulates a non-zero error value on failure, and returns 0 on success.
Errors
The DbEnv::set_tx_recover method may fail and throw an exception or return a non-zero error for the following conditions:
- EINVAL
- An invalid flag value or parameter was specified.
Called after DbEnv::open was called.
The DbEnv::set_tx_recover method may fail and throw an exception or return a non-zero error for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the DbEnv::set_tx_recover method may fail and either
return DB_RUNRECOVERY or throw an exception encapsulating
DB_RUNRECOVERY, in which case all subsequent Berkeley DB calls will fail
in the same way.
Class
DbEnv, DbTxn
See Also
DbEnv::set_tx_max,
DbEnv::set_tx_recover,
DbEnv::set_tx_timestamp,
DbTxn::abort,
DbEnv::txn_begin,
DbEnv::txn_checkpoint,
DbTxn::commit,
DbTxn::discard,
DbTxn::id,
DbTxn::prepare,
DbEnv::txn_recover,
DbTxn::set_timeout
and
DbEnv::txn_stat.
Copyright Sleepycat Software
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