Search notes:

ORA-14452: attempt to create, alter or drop an index on temporary table already in use

The ORA-14452: attempt to create, alter or drop an index on temporary table already in use error message is thrown when it is tried to perform a DDL statement on a global temporary table with on commit preserve rows when the session trying to do the DDL has already made a DML on the table.
In order to execute the DDL, the table must first be either truncated or the session must be exited.

Dropping GTT with data in it

create global temporary table tq84_gtt(n number) on commit preserve rows;
insert into tq84_gtt values (42);
drop table tq84_gtt;
-- ORA-14452: attempt to create, alter or drop an index on temporary table already in use
truncate table tq84_gtt;
drop table tq84_gtt;
-- Table TQ84_GTT dropped.

See also

Other 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...', 1761458994, '216.73.216.115', 'Mozilla/5.0 App...', NULL) #2 /home/httpd/vhosts/renenyffenegger.ch/httpsdocs/notes/development/databases/Oracle/errors/ORA-14452_attempt-to-create-alter-or-drop-an-index-on-temporary-table-alredy-in-use(49): insert_webrequest() #3 {main} thrown in /home/httpd/vhosts/renenyffenegger.ch/php/web-request-database.php on line 78