Как узнать номер автоинкремента при вставке новой записи?
Falk0ner, вс, 06/07/2008 - 15:34.
We have a table in MsAccess like :
Test, Fields (id=autoinc, name=text);
First we have to have a function like the one below :
function GetLastInsertID: integer;
begin
// datResult = TADODataSet
datResult.Active := False;
datResult.CommandText := 'select @@IDENTITY as [ID]';
datResult.Active := True;
Result := datResult.FieldByName('id').AsInteger;
datResult.Active := False;
end;
begin
// datResult = TADODataSet
datResult.Active := False;
datResult.CommandText := 'select @@IDENTITY as [ID]';
datResult.Active := True;
Result := datResult.FieldByName('id').AsInteger;
datResult.Active := False;
end;
Now before getting the last inserted record record id = autoincrement field, in other words calling the above function. You have to do a SQL insert like the following
procedure InsertRec;
begin
// datCommand = TADOCommand
datCommand.CommandText := 'insert into [test] ( [name] ) values ( "Test" )';
datCommand.Execute;
end;
begin
// datCommand = TADOCommand
datCommand.CommandText := 'insert into [test] ( [name] ) values ( "Test" )';
datCommand.Execute;
end;
Now if we like to know which is the last autoinc value ( notice that the getlastinsertid proc. only works after the insertrec proc)
procedure Test;
begin
InsertRec;
Showmessage(format('lastinsertid : %d', [GetLastInsertID]));
end;
begin
InsertRec;
Showmessage(format('lastinsertid : %d', [GetLastInsertID]));
end;
Hope you can make this work, it works for me, any questions feel free to ask
Взято с Delphi Knowledge Base: http://www.baltsoft.com/
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