How to cancel a long-running Database operation?

Question

Currently working with Oracle, but will also need a solution for MS SQL.

I have a GUI that allows users to generate SQL that will be executed on the database. This

Answer 1

I have tried both Cancel and Close with ADO 2.8 and SQLOLEDB or SQL Server native client. With Cancel, the recordset stops fetching data, but in the backround the reading from the server continues and consumes memory from the application. In a 32 bit application it can happen that you get an "out of memory" message some minutes later. When I close the recordset (or the connection, with or without Cancel before), ADO 2.8 waits until all records are fetched.

I don't know if ADO.NET does it better, but I think it's a good idea to monitor memory and network access after Cancel/Close to be sure that ADO really stops reading data.