BaseDatabase Members

BerkeleyDB

The BaseDatabase type exposes the following members.

Methods

  NameDescription
CloseOverloaded.

Although closing a database will close any open cursors, it is recommended that applications explicitly close all their Cursor objects before closing the database. The reason why is that when the cursor is explicitly closed, the memory allocated for it is reclaimed; however, this will not happen if you close a database while cursors are still opened.

The same rule, for the same reasons, hold true for Transaction objects. Simply make sure you resolve all your transaction objects before closing your database handle.

Because key/data pairs are cached in memory, applications should make a point to always either close database handles or sync their data to disk (using Sync()()() before exiting, to ensure that any data cached in main memory are reflected in the underlying file system.

When called on a database that is the primary database for a secondary index, the primary database should be closed only after all secondary indices referencing it have been closed.

When multiple threads are using the object concurrently, only a single thread may call the Close method.

The object may not be accessed again after Close is called, regardless of its outcome.

CursorOverloaded.
DeleteOverloaded.
Dispose
Release the resources held by this object, and close the database if it's still open.
Equals
Determines whether the specified Object is equal to the current Object.
(Inherited from Object.)
ExistsOverloaded.
GetOverloaded.
GetBothOverloaded.
GetHashCode
Serves as a hash function for a particular type.
(Inherited from Object.)
GetType
Gets the Type of the current instance.
(Inherited from Object.)
PrintFastStatsOverloaded.
The statistical information is described by the BTreeStats, HashStats, QueueStats, and RecnoStats classes.
PrintStatsOverloaded.
The statistical information is described by the BTreeStats, HashStats, QueueStats, and RecnoStats classes.
RemoveOverloaded.

Applications should never remove databases with open DB handles, or in the case of removing a file, when any database in the file has an open handle. For example, some architectures do not permit the removal of files with open system handles. On these architectures, attempts to remove databases currently in use by any thread of control in the system may fail.

Remove should not be called if the remove is intended to be transactionally safe; RemoveDB(String, Boolean) should be used instead.

RenameOverloaded.

Applications should not rename databases that are currently in use. If an underlying file is being renamed and logging is currently enabled in the database environment, no database in the file may be open when Rename is called. In particular, some architectures do not permit renaming files with open handles. On these architectures, attempts to rename databases that are currently in use by any thread of control in the system may fail.

Rename should not be called if the rename is intended to be transactionally safe; RenameDB(String, String, Boolean) should be used instead.

Sync
Flush any cached information to disk.
ToString
Returns a String that represents the current Object.
(Inherited from Object.)
TruncateOverloaded.
When called on a database configured with secondary indices, Truncate will truncate the primary database and all secondary indices. A count of the records discarded from the primary database is returned.

Properties

  NameDescription
AutoCommit
If true, all database modification operations based on this object will be transactionally protected.
CacheSize
The size of the shared memory buffer pool -- that is, the cache.
Creation
The CreatePolicy with which this database was opened.
DatabaseName
The name of this database, if it has one.
DoChecksum
If true, do checksum verification of pages read into the cache from the backing filestore.
EncryptAlgorithm
The algorithm used by the Berkeley DB library to perform encryption and decryption.
Encrypted
If true, encrypt all data stored in the database.
Endianness
The database byte order.
ErrorFeedback
The mechanism for reporting detailed error messages to the application.
ErrorPrefix
The prefix string that appears before error messages issued by Berkeley DB.
Feedback
Monitor progress within long running operations.
FileName
The filename of this database, if it has one.
FreeThreaded
If true, the object is free-threaded; that is, concurrently usable by multiple threads in the address space.
HasMultiple
If true, the object references a physical file supporting multiple databases.
InHostOrder
If true, the underlying database files were created on an architecture of the same byte order as the current one. This information may be used to determine whether application data needs to be adjusted for this architecture or not.
NoMMap

If true, this database is not mapped into process memory.

See MMapSize for further information.

NonDurableTxns
If true, Berkeley DB will not write log records for this database.
Pagesize
The database's current page size.
Priority
The cache priority for pages referenced by this object.
ReadOnly
If true, this database has been opened for reading only. Any attempt to modify items in the database will fail, regardless of the actual permissions of any underlying files.
ReadUncommitted
If true, this database supports transactional read operations with degree 1 isolation. Read operations on the database may request the return of modified but not yet committed data.
Transactional
If true, this database has been opened in a transactional mode.
Truncated
If true, the underlying file was physically truncated upon open, discarding all previous databases it might have held.
Type
The type of the underlying access method (and file format). This value may be used to determine the type of the database after an Open(String, DatabaseConfig).
UseMVCC
If true, the database was opened with support for multiversion concurrency control.

See Also