Hi @ryanmoon32,

You cannot include scalar values directly in BQL queries. You need to use a constant class, like this one:

public class myConstant : Constant<string> { public myConstant() : base(“A”) { } }

It just so happens there’s already a set of constants defined for reason code usage in the ReasonCodeUsages class; you don’t need to redefine it. Here’s how it should look:

aPXSelector(typeof(Search<ReasonCode.reasonCodeID, Where<ReasonCode.usage, Equal<ReasonCodeUsages.adjustment>>>), typeof(ReasonCode.reasonCodeID), typeof(ReasonCode.descr))]

Thanks @Gabriel Michaud 
For future reference, where would that class for the constant go inside of my customization project?

Code - Create Code File - New Graph or Code File?

Hi @ryanmoon32  Yes.

As per standard practice, you need to create the separate class file (Constants.cs), where you can maintain all constants of your project and access it from here.