Fatal error: Uncaught PDOException: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'a' in 'where clause' in /home/storage/6/df/99/bibliotecacelsof1/public_html/interna_A.php:56 Stack trace: #0 /home/storage/6/df/99/bibliotecacelsof1/public_html/interna_A.php(56): PDO->query('SELECT\n ...') #1 /home/storage/6/df/99/bibliotecacelsof1/public_html/interna.php(10): include('/home/storage/6...') #2 {main} thrown in /home/storage/6/df/99/bibliotecacelsof1/public_html/interna_A.php on line 56