MySQL concepts: session vs connection

Xiaofeng Tang picture Xiaofeng Tang · Jan 10, 2012 · Viewed 9.9k times · Source

I'm a bit confused by MySQL concepts: session vs connection.

When talking about connecting to MySQL, we use connection terminology, connection pool, etc.

However in the MySQL online doc: http://dev.mysql.com/doc/refman/4.1/en/server-system-variables.html it talks about session variables.

They are quite similar. How to distinguish them?

Thanks in advance.

Answer

newtover picture newtover · Jan 10, 2012

A session is just a result of a successful connection. Any MySQL client requires some connection settings to establish a connection and after the connection has been established it acquires a connection id (thread id) and some context which is called session.