#1066 - 不唯一的表/别名:

Question

你能帮帮我吗？我有这个SQL查询:

SELECT l.url 
FROM (b INNER JOIN links ON b.parent_id = l.id) 
INNER JOIN b ON l.id = b.link 
WHERE l.url LIKE 'http://domain%' LIMIT 0, 30

不知何故,它说

#1066 - Not unique table/alias: b

Answer 1

你似乎是从同一张桌子中选择两次.这些事件中的每一个都需要自己的别名:

SELECT
    l.url
FROM
    b as b1 /* <-- */
    INNER JOIN links as l
      ON b1.parent_id = l.id
    INNER JOIN b as b2 /* <-- */
      ON l.id = b2.link
WHERE l.url LIKE 'http://domain%' LIMIT 0, 30

请注意,我还l为links表添加了缺少的别名.