Hi Hari,
GoodData uses MAQL (Multidimensional Analytical Query Language) instead of DAX for creating metrics and calculations.
MAQL is a query language specific to the GoodData platform and is used to define metrics, filters, and other calculations. I recommend checking the resources below for more details:
MAQL - Analytical Query Language | GoodData Free
If you’re using GoodData Cloud, see:
MAQL and Multidimensionality | GoodData Cloud Native
You can also take advantage of our free course in our University: GoodData University