PHP跟踪当前用户

Question

I have an website with editable databases. I am trying to implement a simple system that ensures no one is editing the same row at the same time. I cannot find any information on how to pass PHP variables to different users or how to store them globally on the server.

Ex: User 1 is editing Row ABC

User 2 attempts to edit Row ABC

User 2 is warned that someone is editing Row ABC

The ideal solution in my mind is

User 1 is editing Row ABC -> Create PHP var for that row to lock it

User 2 attempts to edit Row ABC -> A check is done to see if that PHP var exists and its state (0/1)

How can I pass this value across to different browser sessions and/or users?

Answer 1

You don't need to use PHP vars for this. Just store in the database which row is being edited by which user. When a user starts editing a row.

Implement it with a table called RowLock and give it 2 columns, RowId and UserId . Editing a row is:

• Checks if the row is being edited by another user,
• If it is, access is denied
• If it isn't, put the user id in the RowLock table and then grant access

When they are finished editing the row, UserId is set to null or the the lock is deleted entirely.