如何在MySQL查询的结果中找出特定列的值？

Question

I have a table with the following columns: id, firstname, lastname, category. And let's say i have data with categories like: action, comedy, drama, horror. My query is

SELECT * FROM tablename WHERE firstname LIKE '%John%'

The query will bring all the records that contain 'John' in firstname, and let's assume that the records have different values for categoty: action and comedy only.

How to find out the list with all the values available in category column for this specific search.

Thanks!

Answer 1

If you want a distinct list of categories, where firstname is like John:

SELECT DISTINCT category FROM tablename WHERE firstname LIKE '%John%'