mysql_insert_id issue in concurrency data inserting
concurrency, mysql, mysql-insert-id
Solution
`mysql_insert_id` is completely multi-user safe.It is entirely relies upon the database connection, and you can only have one user per connection....So, as per your question, it returns true id....
From MySql documentation,
The ID that was generated is maintained in the server on a per-connection basis. This means that the value returned by the function to a given client is the first AUTO_INCREMENT value generated for most recent statement affecting an AUTO_INCREMENT column by that client. This value cannot be affected by other clients, even if they generate AUTO_INCREMENT values of their own. This behavior ensures that each client can retrieve its own ID without concern for the activity of other clients, and without the need for locks or transactions.
Problem
How reliable is `mysql_insert_id()` in a competitive condition? I mean when multiple users are inserting data at the same time, will this function return the true ID or it will return other user's inserted data ID? The table engine is MyISAM.