What is the main purpose of using the SUB and END SUB control statements in Qlik?

The main purpose of using the SUB and END SUB control statements in Qlik is to create subroutines. Subroutines are blocks of reusable code that can be called multiple times within a script, helping to organize and streamline the code. This modular approach allows developers to write code once and invoke it wherever necessary, reducing redundancy and making the script easier to maintain and understand.

In Qlik's scripting environment, defining a subroutine with the SUB statement allows you to encapsulate a specific functionality or logic, which can then be executed at different points in the script by calling the subroutine by its name. The END SUB statement marks the end of the subroutine definition.

This structure is essential for implementing tasks that may require the same logic to be executed repeatedly or for structuring complex scripts into manageable sections, making it more efficient to develop and troubleshoot.