MashZone NextGen provides both plain functions as well as analytic functions that you may use in RAQL queries. While some extensions are based on standard SQL definitions, others are RAQL-specific extensions that widens the support of analytic tasks you can tackle. You can also define and add your own plain or analytic functions to RAQL. See Creating new user-defined functions for instructions.
Note that in contrast to the case-insensitive handling of SQL functions, RAQL-specific functions are handled case-sensitively.