Problems with your sql statement.

DESCRIBE category

Out of resources when opening file '/var/tmp/#sql_6f65_1.MAD' (Errcode: 24)cannot describe category
Warning: array_keys() expects parameter 1 to be array, boolean given in /home/webapp/domains/ on line 187

Warning: Invalid argument supplied for foreach() in /home/webapp/domains/ on line 197

Notice: Undefined offset: 1 in /home/webapp/domains/ on line 330

Problems with your sql statement.

SELECT * FROM category WHERE ( = '739')

You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '= '739')' at line 1
Fatal error: Call to a member function countRows() on boolean in /home/webapp/domains/ on line 412