I'm developing a php web application. When I insert a user's information from a html form to a USER table, I also need to insert some data to 2nd table. There's a "contact_id" in 2nd table related with "user_id" (auto_increment) in USER table. But I just don't know how I can get the latest inserted user's ID from USER table and insert it into the 2nd table "contact_id" field.

Please give me some hint.

use the mysql_insert_id() function

Thank you so much. Help me a lot! :-)