ActiveX Data Objects: Difference between revisions

Revision as of 16:08, 5 January 2017

Revision as of 05:50, 16 March 2017

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: The recordset is locked using the adLockOptimistic or adLockPessimistic lock. The data are updated at the data source after the record is changed and the Update method is called.

; Batch

: The recordset is locked using adLockBatchOptimistic and each time Update is called the data are updated in a temporary buffer. Finally, when UpdateBatch is called the data are completely updated back at the data source. This has the advantage of it all being done in memory, and if a problem occurs then UpdateCancel is called and the updates are not sent to the data source.

; Transaction

: If the OLE DB provider allows it, transactions can be used. To start the transaction, the programmer invokes the BeginTrans method and does the required updates. When they are all done, the programmer invokes the CommitTrans method. RollbackTrans can be invoked to cancel any changes made inside the transaction and rollbackroll back the database to the state before the transaction began.

; Record

: This object represents one record in the database and contains a fields collection. A RecordSet consists of a collection of Record objects.