Unknown column 'assets' in 'where clause'

In file /home/u695703520/domains/naelikud.eu/public_html/controllers/universaalnaelikud.php, line 84, function view( "SELECT g.g_shoe_desc, g_shoe_name, (IF (MIN(shoe_price)!=MAX(shoe_price), CONCAT(MIN(shoe_price), CONCAT(' - ',MAX(shoe_price))), shoe_price) ) as shoe_price FROM g_shoe g NATURAL JOIN shoe WHERE type_id = 1 AND (shoe_stock = 1 OR shoe_tellitav IS NOT NULL) AND g.g_shoe_id = assets" )

Stack trace:

#0 system/database.php(84): db_error_out()
#1 controllers/universaalnaelikud.php(21): get_first('SELECT g.g_shoe...')
#2 system/classes/Application.php(83): universaalnaelikud->view()
#3 index.php(10): Application->__construct()
#4 {main}