A family of Microsoft relational database management systems designed for ease of use.
I strongly endorse what Peter and Duane have said. You are currently encoding data in an expression. A fundamental principle of the database relational model is the Information Principle (Codd's Rule #1). This requires that all data be stored as values at column positions in rows in tables, and in no other way.
By storing the data correctly in a table you simply need to join that table to your current table on the Code columns to return the appropriate value.