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Sleepycat Software Berkeley DB Products



MSleepycat Software licenses three different products that use the Berkeley DB technology.9Each product offers a distinct level of database support.FAll three products are included in the single Open Source distribution'of Berkeley DB from Sleepycat Software.>Each product adds services, and new interfaces, to the productthat precedes it in the list. As a result,Fdevelopers can download Berkeley DB and build an application that doesonly single-user,read-only database access,;and then add support for more users and transactions later.

FUsers who distribute Berkeley DB must ensure that they are licensed toDdistribute the Berkeley DB interfaces that they use. Information onElicensing is available directly from Sleepycat Software, as describedEin the Sleepycat Software ContactInformation.#

Berkeley DB Access Methods



YThe Berkeley DB Access Methods product is an embeddable, high-performance data store. ItCsupports multiple concurrent threads of control to read informationmanaged by Berkeley DB.AWhen updates are required, only a single process may be using the database.BThat process may be multi-threaded, but only one thread of control5should be allowed to update the database at any time.BThe Berkeley DB Access Methods does no locking, and so provides noDguarantees of correct behavior if more than one thread of control is updating the database at a time.

5The Berkeley DB Access Methods is intended for use inEsingle-user or read-only applications that can guarantee that no moreEthan one thread of control will ever update the database at any time.

bThis product includes db_open and its methods, and the methods=returned by DB->cursor..

Berkeley DB Concurrent Access Methods



eThe Berkeley DB Concurrent Access Methods product adds multiple-reader, single writer capabilities to\the Berkeley DB Access Methods product, supporting applications that need concurrent updatesIand do not want to implement their own locking protocols. The additionalƒinterfaces in the Berkeley DB Concurrent Access Methods product are db_appinit (using the‚DB_INIT_CDB flag), and db_appexit.

`Berkeley DB Concurrent Access Methods is intended for applications that require occasional write6access to a database that is largely used for reading.1

Berkeley DB Transactional Access Methods



gThe Berkeley DB Transactional Access Methods product adds full transactional support and recoverabilityWto the Berkeley DB Access Methods product. This product includes all of the interfacesin the Berkeley DB library.

fBerkeley DB Transactional Access Methods is intended for applications that require industrial-strengthDdatabase services, including good performance under high-concurrencyFworkloads with a mixture of readers and writers, the ability to commitFor roll back multiple changes to the database at a single instant, andIthe guarantee that even in the event of a catastrophic system or hardware:failure, any committed database changes will be preserved.ÿÿ