MySQL server error report:Array ( [0] => Array ( [message] => MySQL Query Error ) [1] => Array ( [sql] => SELECT distinct g.cat_id, c.cat_name FROM `ecshop`.`ecs_goods` AS g,`ecshop`.`ecs_category` AS c where g.cat_id= c.cat_id and g.city_id= and g.brand_id = 295 order by g.cat_id limit 3 ) [2] => Array ( [error] => You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'and g.brand_id = 295 order by g.cat_id limit 3' at line 1 ) [3] => Array ( [errno] => 1064 ) )