If the cursor is not yet initialized, MovePrevUnique is identical to
MoveLast(LockingInfo). Otherwise, move the cursor to
the previous non-duplicate key in the database, and store the
secondary key and primary key/data pair in Current.
MovePrevUnique will return false if no non-duplicate key/data pairs
exist after the cursor position in the database. If
key, or pkey, or
data is partial DatabaseEntry, its
PartialLen bytes starting
PartialOffset bytes from the beginning
of the retrieved data record are returned as if they comprised the
entire record. If any or all of the specified bytes do not exist
in the record, MovePrevUnique is successful, and any existing bytes
are returned.
Namespace:
BerkeleyDBAssembly: libdb_dotnet52 (in libdb_dotnet52.dll) Version: 5.2.28.0
Syntax
C# |
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public bool MovePrevUnique( DatabaseEntry key, DatabaseEntry pkey, DatabaseEntry data, LockingInfo info ) |
Visual Basic (Declaration) |
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Public Function MovePrevUnique ( _ key As DatabaseEntry, _ pkey As DatabaseEntry, _ data As DatabaseEntry, _ info As LockingInfo _ ) As Boolean |
Visual C++ |
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public: bool MovePrevUnique( DatabaseEntry^ key, DatabaseEntry^ pkey, DatabaseEntry^ data, LockingInfo^ info ) |
Parameters
- key
- Type: BerkeleyDB..::.DatabaseEntry
The retrieved key in secondary db
- pkey
- Type: BerkeleyDB..::.DatabaseEntry
The key of the matching record in primary db
- data
- Type: BerkeleyDB..::.DatabaseEntry
The data of the matching record in primary db
- info
- Type: BerkeleyDB..::.LockingInfo
The locking behavior to use
Return Value
True if the cursor was positioned successfully, false otherwise.Remarks
If positioning the cursor fails, Current will contain
an empty KeyValuePair<(Of <(TKey, TValue>)>).