How to define DB-index for speeding up get_list() queries?

I am using a get_list() via a bean to retrieve records.
I assume a new index would help to speed up the query but I am not entirely sure how to define it that SuiteCRMs $bean->get_list() takes advantage of it.

I have a text field ABC_c in a custom_cstm table which I try to search to find relevant matches.

get_list(“name”, “custom_cstm.ABC_c = ‘$query_name’”);

Would an index over
ABC_C, id_c
suffice or do I need other fields in the list to speed up the query?

If you put your logs in DEBUG mode, you can get the exact SQL query that is being generated from that.

Then you can play with it in the database, use SQL EXPLAIN, and figure out the correct indeces to use.