User-defined functions are functions that you use to organize your code in the body of a policy.

User-defined functions help to decompose a large program into small segments which makes program easy to understand, maintain and debug. If repeated code occurs in a program. Function can be used to include those codes and execute when needed by calling that function.

A user-defined function (UDF) lets you create a function by using a SQL expression or JavaScript code. A UDF accepts columns of input, performs actions on the input, and returns the result of those actions as a value. You can define UDFs as either persistent or temporary.