conditional-execution

SQL Server: How to call a UDF, if available?

Most systems will have a user-defined function (UDF) available. Some will not. i want to use the UDF if it's there: SELECT Users.*, dbo.UserGroupMembershipNames(Users.UserID) AS MemberOfGroupNames FROM Users Otherwise fallback to the acceptable alternative SELECT Users.*, (SELECT TOP 1 thing FROM Something WHERE S...

Controlled execution of computationally expensive tasks

Say you have an application where a user is typing some text and as she types you'd want to perform some expensive computations in the background (related to the text that is being typed). Although you would like to do lots of things, your main priority is that the system responsiveness stay at acceptable levels so the user doesn't notic...