In X++ it is possible to write code that inspects the structure of other X++ code. This is sometimes called reflection or meta-programming. You may wonder why you’d want to do that. Reflection is a very powerful tool and opens a wide array of possibilities. Without it some things would be very hard or even impossible to implement. Just look at the code behind table browser, the unit testing framework, or the data export and import tools. There are several ways to do reflection in X++. I’m going to show an example using the Dictionary. It involves classes whose names start with Dict and SysDict. The latter are subclasses of their respective Dict-class and can be found in the AOT. The goal Suppose you need to analyze the performance of an existing application. You could set up monitoring but you need an indication where to start. The largest tables in the database, i.e. those with most records, are potential performance bottlenecks. For large tables it is important to have the ...