FireDAC.Comp.Client.TFDCustomTransaction.Commit
Delphi
procedure Commit;
C++
void __fastcall Commit();
Contents
Properties
| Type | Visibility | Source | Unit | Parent |
|---|---|---|---|---|
procedure function |
public | FireDAC.Comp.Client.pas FireDAC.Comp.Client.hpp |
FireDAC.Comp.Client | TFDCustomTransaction |
Description
Permanently stores modifications to the data made in the current transaction, and optionally ends the current transactions.
Call Commit to permanently store modifications, such as INSERT / UPDATE / DELETE commands, made in the current transaction to the database.
FireDAC 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 DBMSs, then FireDAC 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 DBMSs a call will invalidate all active result sets (for example, on MS SQL Server 2005).
Example
procedure TForm1.ChangeButtonClick(Sender: TObject);
begin
FDQuery1.Transaction := FDTransaction1;
FDQuery1.SQL.Text := 'update employees set salary = salary * :k where id = :id';
FDTransaction1.StartTransaction;
try
FDQuery1.ExecSQL('', [1.2, 100]);
FDQuery1.ExecSQL('', [1.3, 200]);
FDTransaction1.Commit;
except
FDTransaction1.Rollback;
raise;
end;
end;