Db.cursor
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import com.sleepycat.db.*;
public Dbc cursor(DbTxn txnid, int flags)
throws DbException;
Description
The Db.cursor method
creates a cursor.
If the operation is to be transaction-protected, the txnid
parameter is a transaction handle returned from DbEnv.txn_begin;
otherwise, null.
To transaction-protect cursor operations, cursors must be opened and
closed within the context of a transaction, and the txnid
parameter specifies the transaction context in which the cursor may be
used.
The flags value must be set to 0 or by bitwise inclusively OR'ing together one or
more of the following values:
- Db.DB_DIRTY_READ
- All read operations performed by the cursor may return modified but not
yet committed data. Silently ignored if the Db.DB_DIRTY_READ flag
was not specified when the underlying database was opened.
- Db.DB_WRITECURSOR
- Specify that the cursor will be used to update the database. The
underlying database environment must have been opened using the
Db.DB_INIT_CDB flag.
The Db.cursor method throws an exception that encapsulates a non-zero error value on
failure.
Errors
The Db.cursor method may fail and throw an exception encapsulating a non-zero error for the following conditions:
- EINVAL
- An invalid flag value or parameter was specified.
The Db.cursor method may fail and throw an exception for errors specified for other Berkeley DB and C library or system methods.
If a catastrophic error has occurred, the Db.cursor method may fail and
throw a DbRunRecoveryException,
in which case all subsequent Berkeley DB calls will fail in the same way.
Class
Dbc
See Also
Database Cursors and Related Methods
Copyright Sleepycat Software
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