PHP error happened

Technical information
Error type8192
Error descriptionmysql_connect(): The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead
URLwww.kiwanisrosefloat.com/registration/kiwanis_rose_parade_float_registration_page_add.php?
Error file/home/krf/krf/registration/include/dbconnection.php
Error line9
SQL query