syntax error: select tb1.title,tb1.description,tb1.keywords,tb1.ten,tb2.ten as cat,tb1.id_cat from table_cat_footer as tb1 LEFT JOIN table_product_cat as tb2 ON tb1.id_cat=tb2.id where tb1.hienthi=1 and tb1.com='cat2' and tb1.id='211' Error: 1054Line: Unknown column 'tb2.ten' in 'field list'