Permanently stores modifications to the data made in the current transaction, and optionally ends the current transactions.
Call Commit to permanently store modifications, like a INSERT's / UPDATE's / DELETE's, made in current transaction to the database.
AnyDAC supports nested transactions, so the current transaction is the one started with most recent StartTransaction call. If the database does not support nested transactions, like most of DBMS's, then AnyDAC will emulate nested transactions using savepoints.
Before calling Commit, an application may check the status of the Active property. If an application calls Commit and there is no current transaction, an exception is raised.
A Commit call on Interbase / Firebird will close and unprepare all datasets and commands, associated with this transaction object. On some other DBMS's a call will invalidate all active result sets. For example, on MS SQL Server 2005.
procedure TForm1.ChangeButtonClick(Sender: TObject); begin ADQuery1.Transaction := ADTransaction1; ADQuery1.SQL.Text := 'update employees set salary = salary * :k where id = :id'; ADTransaction1.StartTransaction; try ADQuery1.ExecSQL('', [1.2, 100]); ADQuery1.ExecSQL('', [1.3, 200]); ADTransaction1.Commit; except ADTransaction1.Rollback; raise; end; end;
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