How to Use find_in_set in Mysql

Example of using find_in_set in Mysql: a field (purview) in the user table indicates the user's permission to save all the user's permission IDs to this field. For example, the following five permissions are available: 1, 2, 3, 4, and 5: select * from user where find_in_set ('1', purview) which users have the permission id of 1 ); SQL statement SQL explanation: finds information about all users with the 1 permission. In this way, the purpose of designing a data table is to reduce the number of tables, but it will increase the difficulty of updating!