I queried data in app_user table and found that almost cases user_key = lower_user_name.
However some cases user_key field value is ID##### (##### is value of ID field).
Example:
- ID = 12345
- user_key = ID12345
- lower_user_name = duongtt
Let's try:
SELECT * FROM `app_user` u WHERE u.`user_key` LIKE '%ID%';
I ensure that all users logged in with their username.
Which case user_key in table app_user has value as ID?