I have written an application that takes in a fixed-width file (thanks in no small part to advice I recieved in a seperate thread) and then dissasembles each line, runs a fairly meaty SQL SELECT ...

You can use VB.NET or C# to write procedural code and create user-defined types and aggregates in SQL Server.

MS SQL doesn't allow that, and I seriously doubt that MySQL does either. You're probably going to have to use string concatenation, unfortunately.

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