How to find the related items from different tables?
Tell me how to find the related items from different tables if one table does not have a connection.
There are tables:
1) wall - id, message, attachments
2) attachments - id, path
the table is the wall in the attachments field contains the id of the attachment and the problem is that there may be several pieces (for example: 1,324,5342). Please tell me how can I map values, or what changes to make to the table structure, to realize the idea more correctly?