MySql Thread

What are the Performance and Scalability characteristics of MySQL?What is difference between mysql_connect and mysql_pconnect?

From the manual ( :

mysql_pconnect() acts very much like mysql_connect() with two major differences.

First, when connecting, the function would first try to find a (persistent) link that’s already open with the same host, username and password. If one is found, an identifier for it will be returned instead of opening a new connection.

Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (mysql_close() will not close links established by mysql_pconnect()).

This type of link is therefore called ‘persistent’.

And you shouldn’t use either. From the same page:


This extension is deprecated as of PHP 5.5.0, and will be removed in the future. Instead, the MySQLi or PDO_MySQL extension should be used

guido is correct. My concern is your use of “thread”. Do you mind giving us a use case? PHP itself doesn’t really have great support for multi threading.