Your SQL is going to have to read the custom field, the field configuration, the field context, the workflow (which it will then have to parse for screens), the issue type screen scheme and then screens to answer that question. You are looking at a query against 20+ tables for every project to tell you something you probably don't need to know and can do much faster in the UI anyway. Most of us here aren't going to spend the several hours it's going to take to work out such a query.
Using SQL to do anything in Jira is always the wrong way to do it.
Please could you tell us what you are trying to achieve? Why do you think you want to run this SQL?
