Question

This is propably a very easy question.

But i cant fix it.
I try an update if @ID = column id, else insert all.

Only this one doesn’t work if i put it all in one sentence

Cmd.CommandText = "UPDATE Locatie SET (Longitude = @Longitude, Latitude = @Latitude, Timestamp = @Timestamp) WHERE ID=@ID IF @@ROWCOUNT=0 INSERT INTO Locatie VALUES (@ID, @Longitude, @Latitude, @Timestamp)"

Answer 1

This should work just fine

Cmd.CommandText = "IF EXISTS (SELECT 1 FROM Locatie WHERE Id = @Id) " & Environment.NewLine & _
                  "  BEGIN UPDATE Locatie SET Longitude = @Longitude, Latitude = @Latitude, Timestamp = @Timestamp WHERE ID=@Id END " & Environment.NewLine & _
                  "ELSE " & Environment.NewLine & _
                  "   BEGIN INSERT INTO Locatie VALUES (@ID, @Longitude, @Latitude, @Timestamp) END "

Although you are probably better off (for maintainability) using a stored procedure.