Error Message

[renatofdj]

I'm having this problem on my joomla 2.5, when trying to create a category appears this error message

Warning: mysql_num_rows (): supplied argument is not a valid MySQL result resource in / home / renatodj / public_html / libraries / joomla / database / database / mysql.php on line 293

Warning: mysql_num_rows (): supplied argument is not a valid MySQL result resource in / home / renatodj / public_html / libraries / joomla / database / database / mysql.php on line 293

What is this problem?

Thank you all!

[Benno]

Hi,
see: 2. Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource https://www.phoca.cz/documents/50-phoca/ ... al-advices

Kind regards,
Benno