INSERT INTO `book_members` (`userid`, `password`, `username`, `email`, `phone`, `photo`) 
VALUES ('info', md5('info'), '컴퓨터정보', 'info@ansan.ac.kr', '+82314006971', NULL);<br />
<b>Fatal error</b>:  Uncaught mysqli_sql_exception: Duplicate entry 'info' for key 'userid' in /users/2019/i1919004/public_html/2022/WebDB/mysql_test.php:10
Stack trace:
#0 /users/2019/i1919004/public_html/2022/WebDB/mysql_test.php(10): mysqli_query()
#1 {main}
  thrown in <b>/users/2019/i1919004/public_html/2022/WebDB/mysql_test.php</b> on line <b>10</b><br />