How to find rows>columns combinations with Cross Join? [SQL]
问题 I want to create a combination of items from different categories ids. Can you help me? table +---------+-------------+------------+ | post_id | category_id | post_title | +---------+-------------+------------+ | 1 | 1 | Red | | 2 | 1 | Black | | 3 | 2 | Medium | | 4 | 3 | Male | | 5 | 3 | Female | +---------+-------------+------------+ The query results I want is as follows: Red-Medium-Male Black-Medium-Male Red-Medium-Female Black-Medium-Female For example, if there were items belonging to