Question

我有以下查询：

 SELECT c.`entity_id`,c. p.`name` as parent_id, c.`name`
  FROM category c
  LEFT JOIN category p WHERE c.`parent_id = p.id
  WHERE c.is_active = 1
  ORDER BY c.parent_id ASC, c.position ASC;

但是我在第一个WHERE子句上遇到错误，有人能在这里发现错误吗？感谢

Answer 1

您已添加两次where子句。请尝试以下方法：

SELECT c.`entity_id`,c. p.`name` as parent_id, c.`name`
FROM category c
  LEFT JOIN category p on c.`parent_id = p.id
  Where c.is_active = 1
  ORDER BY c.parent_id ASC, c.position ASC;

mySQL：左连接问题

1 个答案: