Permanently stores modifications to the data made in the current transaction, without ending the current transaction.
Call CommitRetaining to permanently store modifications, like a INSERT's / UPDATE's / DELETE's, made in current transaction to the database without finishing transaction.
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. CommitRetaining is usefull only for main transaction, not for nested ones.
The CommitRetaining call is the shortcut to Transaction.CommitRetaining, if Transaction property is assigned. Otherwise CommitRetaining will operate on default connection transaction.
Before calling CommitRetaining, an application may check the status of the InTransaction property. If an application calls CommitRetaining and there is no current transaction, an exception is raised.
procedure TForm1.DoThatButtonClick(Sender: TObject); begin ADConnection1.StartTransaction; try if CustomerQuery.Locate('ID', ) then begin CustomerQuery.Edit; CustomerQuery.FieldByName('status').AsString := 'top'; CustomerQuery.Post; ADConnection1.ExecSQL('delete from debt where CustID = 100'); ADConnection1.CommitRetaining; end; except ADConnection1.RollbackRetaining; raise; end; end;
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