Call to undefined function mysql_query()

    #0 /srv/www/saint-etiennetourisme.com/wp-content/themes/otsaintetienne/header.php(69): NoewpDatabase->select('SELECT * FROM s...')
#1 /srv/www/saint-etiennetourisme.com/wp-includes/template.php(688): require_once('/srv/www/saint-...')
#2 /srv/www/saint-etiennetourisme.com/wp-includes/template.php(647): load_template('/srv/www/saint-...', true)
#3 /srv/www/saint-etiennetourisme.com/wp-includes/general-template.php(45): locate_template(Array, true)
#4 /srv/www/saint-etiennetourisme.com/wp-content/themes/otsaintetienne/page.php(37): get_header()
#5 /srv/www/saint-etiennetourisme.com/wp-includes/template-loader.php(74): include('/srv/www/saint-...')
#6 /srv/www/saint-etiennetourisme.com/wp-blog-header.php(19): require_once('/srv/www/saint-...')
#7 /srv/www/saint-etiennetourisme.com/index.php(17): require('/srv/www/saint-...')
#8 {main}