Search notes:

ORA-03050: invalid identifier: is a reserved word

With «improved» error messages, the following select statement throws ORA-03050: invalid identifier: "USER" is a reserved word. 
select tus.USER from v$tempseg_usage tus;

See also

ORA-03050 seems to be the «improved» error message for ORA-01747: invalid user.table.column, table.column, or column specification
v$reserved_words
Oracle Error Messages

Index

Fatal error: Uncaught PDOException: SQLSTATE[HY000]: General error: 8 attempt to write a readonly database in /home/httpd/vhosts/renenyffenegger.ch/php/web-request-database.php:78 Stack trace: #0 /home/httpd/vhosts/renenyffenegger.ch/php/web-request-database.php(78): PDOStatement->execute(Array) #1 /home/httpd/vhosts/renenyffenegger.ch/php/web-request-database.php(30): insert_webrequest_('/notes/developm...', 1759429871, '216.73.216.42', 'Mozilla/5.0 App...', NULL) #2 /home/httpd/vhosts/renenyffenegger.ch/httpsdocs/notes/development/databases/Oracle/errors/ORA-03050_invalid-identifier_is-a-reserved-word(43): insert_webrequest() #3 {main} thrown in /home/httpd/vhosts/renenyffenegger.ch/php/web-request-database.php on line 78