MySQL error: Unknown column 'product_img' in 'where clause'
Query: SELECT `id`, `alt_url`, 'categories' as `table` FROM `ap_categories` WHERE `alt_url`='js/'+product_img+'/' OR `alt_url`='js/'+product_img+'' OR `alt_url`='js/'+product_img+'/' OR `alt_url`='js/'+product_img+'' UNION SELECT `id`, `alt_url`, 'products' as `table` FROM `ap_products` WHERE `alt_url`='js/'+product_img+'/' OR `alt_url`='js/'+product_img+'' OR `alt_url`='js/'+product_img+'/' OR `alt_url`='js/'+product_img+'' UNION SELECT `id`, `alt_url`, 'articles' as `table` FROM `ap_articles` WHERE `alt_url`='js/'+product_img+'/' OR `alt_url`='js/'+product_img+'' OR `alt_url`='js/'+product_img+'/' OR `alt_url`='js/'+product_img+''
/js/'+product_img+'/