Functions and Operators¶
The DSL offers a number of builtin operators and functions to be used within the query expressions allowing to define a complex ETL process to be executed on the physical data sources by the particular feed providers.
Attention
The actual set of available functions is at this point rather limited focusing merely on the concept demonstration.
Aggregate functions that operate on a 

Comparison functions and operators. 

Conversion functions. 

Date and time manipulation functions. 

Logical operators. 

Mathematical functions and operators. 

Functions that perform calculations across rows of the query result. 