Search notes:

ORA-65503: cannot send or receive temporary LOB locators over a database link

This statement is ok. 
select sql_text     from v$sql@db_far_away;
sql_fulltext is a CLOB and cannot be transmitted over a database link: 
select sql_fulltext from v$sql@db_far_away;
-- ORA-65503: cannot send or receive temporary LOB locators over a database link
-- ORA-02063: preceding line from XYZ

TODO

I was unable to replicate the error message in 23c.

See also

LOB datatypes
Database links
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...', 1788389382, '216.73.217.21', 'Mozilla/5.0 App...', NULL) #2 /home/httpd/vhosts/renenyffenegger.ch/httpsdocs/notes/development/databases/Oracle/errors/ORA-65503_cannot-send-or-receive-temporary-LOB-locators-over-a-database-link(54): insert_webrequest() #3 {main} thrown in /home/httpd/vhosts/renenyffenegger.ch/php/web-request-database.php on line 78