In PostgreSQL database’s table T, items_current_order field and items_next_order field contain comma-separated strings having duplicate characters and enclosed by braces:

We need to add a computed column named count to the table. Rule: Split items_current_order field and items_next_order field respectively into a set having duplicate members and count members of their intersection.

Write the following SPL code:

derive() function adds a computed column to A1’s table. #3 represents the 3rd field; we can also use name to represent the field. split() function splits each string; @c option means using the comma to separate the string. ^ is the operator for computing intersection.

Source:https://stackoverflow.com/questions/78453352/how-to-get-count-values-array1-in-array2