mysql_insert_id and mysql_connect & mysql_pconnect?

[searain]

mysql_insert_id() will return me the the last auto_increment id from the last insert.

It is supposed to call right after the insert statement.

From mysql document

"The last ID that was generated is maintained in the server on a per-connection basis. This means the value the function returns to a given client is the most recent AUTO_INCREMENT value generated by that client. The value cannot be affected by other clients, even if they generate AUTO_INCREMENT values of their own. This behavior ensures that you can retrieve your own ID without concern for the activity of other clients, and without the need for locks or transactions."

How the logics work here if I use it in php?

If two people use the same web site php page to connect to the mysql database. Are they consdiered as one same mysql user?

So if they both issue the insert at the same time, will the mysql_insert_id() get confused?

Or they are the same user but different connection thread, so the mysql_insert_id() will not get confused?

Does it make any difference if I use mysql_connect or mysql_pconnect when calling mysql_insert_id()?

If my last insert failed, did I get the last successful insert of my connection? Or did I get the last successful insert id of this user?

Thanks!

[robert_w_ark]

I'm not too sure about your mysql_insert_id. However, mysql_connect will open a NEW connection to the mysql database. mysql_pconnect is a persistant connect, or will find an existing connection to the mysql database.

I do suggest that you use mysql_connect and mysql_close on each page. I have heard that it is a bit faster, and I have tested that it is. Hope this helps, -Rob

[searain]

If based on mysql said, that mysql_insert_id() is based on per connection.

Then if I use persistent connection, it will create troubles for mysql_insert_id(),

say client_1 get the connection, insert an record, and then call the mysql_insert_id() to get the last auto_increment id.

At the same time client_2 is doing the same thing, Since if I use persistent connection, the client_2 may get the same connection as client_1 get.

MySQL sees client_1 and client_2 as one collection, and the mysql_insert_id() called by client_1 and client_2 could be switched, if the insert() happens at the same time.

Will persistent connection confused the mysql_insert_id() for two different clients's insert activitiy, if so will persistent connection have other dangerous factors for php web appliaction?

Thanks!