Dbc::count
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#include <db_cxx.h>
int
Dbc::count(db_recno_t *countp, u_int32_t flags);
Description
The Dbc::count method returns a count of the number of duplicate data
items for the key to which the
cursor refers, into the memory location to which countp refers.
If the underlying database does not support duplicate data items, the
call will still succeed and a count of 1 will be returned.
The flags parameter is currently unused, and must be set to 0.
If the cursor argument is not yet initialized, the Dbc::count method either returns EINVAL or throws an exception that encapsulates EINVAL.
Otherwise, the Dbc::count 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 Dbc::count 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 Dbc::count method may fail and
either return DB_RUNRECOVERY or 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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