使用AND＆amp;时，Mysql排除第一个参数或者在同一个查询中？

Question

我试图执行这个非常简单的查询。

  

links_public 1 = show

     

links_public 0 =不显示

但是，当运行下面的查询时，它仍会返回links_public设置为0的所有行。

 SELECT *
 FROM links
 WHERE links_public = '1'
 AND links_description LIKE '%$filter%'
 OR links_created_by LIKE '%$filter%'
 OR links_link LIKE '%$filter%'
 ORDER BY links_created DESC

Answer 1

尝试使用一些括号。

像

这样的东西

 SELECT *
 FROM links
 WHERE links_public = '1'
 AND (links_description LIKE '%$filter%'
 OR links_created_by LIKE '%$filter%'
 OR links_link LIKE '%$filter%')
 ORDER BY links_created DESC

你拥有它的方式，它被视为

SELECT *
 FROM links
 WHERE (links_public = '1'
 AND links_description LIKE '%$filter%')
 OR links_created_by LIKE '%$filter%'
 OR links_link LIKE '%$filter%'
 ORDER BY links_created DESC

查看12.3.1. Operator Precedence

Answer 2

更改

SELECT *
 FROM links
 WHERE links_public = '1'
 AND links_description LIKE '%$filter%'
 OR links_created_by LIKE '%$filter%'
 OR links_link LIKE '%$filter%'
 ORDER BY links_created DESC

到

SELECT *
 FROM links
 WHERE links_public = '1'
 AND ( links_description LIKE '%$filter%'
 OR links_created_by LIKE '%$filter%' OR links_link LIKE '%$filter%' )
 ORDER BY links_created DESC

Answer 3

OR正在创建问题。您需要使用（）来分组条件。你应该使用： -

SELECT *
 FROM links
 WHERE links_public = '1'
 AND (links_description LIKE '%$filter%'
 OR links_created_by LIKE '%$filter%' OR links_link LIKE '%$filter%' )
 ORDER BY links_created DESC

Answer 4

放置括号，然后尝试：

SELECT *
 FROM links
 WHERE (links_public = '1')
 AND (links_description LIKE '%$filter%'
 OR links_created_by LIKE '%$filter%'
 OR links_link LIKE '%$filter%')
 ORDER BY links_created DESC