Retrieve a key/data pair from the database. In the presence of
duplicate key values, Get will return the first data item for
key. If the data is a partial
DatabaseEntry, PartialLen
bytes starting PartialOffset bytes
from the beginning of the retrieved data record are returned as
if they comprise the entire record. If any or all of the specified
bytes do not exist in the record, Get 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 KeyValuePair<DatabaseEntry, DatabaseEntry> Get( DatabaseEntry key, DatabaseEntry data, Transaction txn ) |
Visual Basic (Declaration) |
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Public Function Get ( _ key As DatabaseEntry, _ data As DatabaseEntry, _ txn As Transaction _ ) As KeyValuePair(Of DatabaseEntry, DatabaseEntry) |
Visual C++ |
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public: KeyValuePair<DatabaseEntry^, DatabaseEntry^> Get( DatabaseEntry^ key, DatabaseEntry^ data, Transaction^ txn ) |
Parameters
- key
- Type: BerkeleyDB..::.DatabaseEntry
The key to search for
- data
- Type: BerkeleyDB..::.DatabaseEntry
The retrieved data
- txn
- Type: BerkeleyDB..::.Transaction
txn is a Transaction object returned from BeginTransaction()()(); if the operation is part of a Berkeley DB Concurrent Data Store group, txn is a handle returned from BeginCDSGroup()()(); otherwise null.
Return Value
A KeyValuePair<(Of <(TKey, TValue>)>) whose Key parameter is key and whose Value parameter is the partially retrieved bytes in the data.Remarks
If txn is null and the operation occurs in
a transactional database, the operation will be implicitly
transaction protected.
Exceptions
Exception | Condition |
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BerkeleyDB..::.NotFoundException | A NotFoundException is thrown if key is not in the database. |
BerkeleyDB..::.KeyEmptyException | A KeyEmptyException is thrown if the database is a QueueDatabase or RecnoDatabase database and key exists, but was never explicitly created by the application or was later deleted. |