Question

我知道一个非常疯狂的查询，但是当我运行它时，它会返回所有匹配，无论字段mvideo是否为空。

查询是：

SELECT * 
FROM `weaponsprojects` 
WHERE mvideo != "" 
  AND credit7 = "' .$person. '" 
   OR credit2 = "' .$person. '" 
   OR credit3 = "' .$person. '" 
   OR credit4 = "' .$person. '" 
   OR credit5 = "' .$person. '"
   OR credit6 = "' .$person. '"
   OR credit1 = "' .$person. '"
   OR credit8 = "' .$person. '"
   OR credit9 = "' .$person. '"
   OR credit10 = "' .$person. '"
   OR credit11 = "' .$person. '"
   OR credit12 = "' .$person. '"
   ORDER BY usort'

并且当任何信用等于该人但它完全忽略mvideo部分时它返回。这是为什么？

编辑：该字段不是NULL，只是简单地清空空格

Answer 1

我认为WHERE条件在逻辑上有缺陷......你需要一些优先权，如下：

SELECT * 
FROM `weaponsprojects` 
WHERE mvideo != "" 
  AND (credit7 = "' .$person. '" 
   OR credit2 = "' .$person. '" 
   OR credit3 = "' .$person. '" 
   OR credit4 = "' .$person. '" 
   OR credit5 = "' .$person. '"
   OR credit6 = "' .$person. '"
   OR credit1 = "' .$person. '"
   OR credit8 = "' .$person. '"
   OR credit9 = "' .$person. '"
   OR credit10 = "' .$person. '"
   OR credit11 = "' .$person. '"
   OR credit12 = "' .$person. '")
   ORDER BY usort'

添加(和)我们告诉WHERE语句：“mvideo不是空的，并且与OR个语句之一匹配“

Mysql查询忽略NULL和空字段

1 个答案: