Question

是否可以像这样编写查询？

SELECT a FROM Action a WHERE a.name = "name" WHERE a.namesafe = "namesafe"

Answer 1

您的SQL有一些错误

您正在选择表别名而不是列。SELECT a FROM Action a。可能你错过了.*。
使用双引号"代替单'。

可能是你要找的是这个，

SELECT a.* FROM Action a WHERE a.name = 'name' AND a.namesafe = 'namesafe'

但是，您可以使用两个 WHERE 。但这会很棘手。

SELECT 
    T.* 
FROM 
    (
        SELECT 
            a.* 
        FROM 
            Action a 
        WHERE 
            a.name = 'name'
    ) AS T 
WHERE 
    T.namesafe = 'namesafe'

Answer 2

不会抛出错误，但是如果你想使用两个搜索条件，你可以使用它。 SELECT a FROM Action a WHERE a.name = "name" and a.namesafe = "namesafe"

Answer 3

如果您希望它们都使用AND：

SELECT a FROM Action a WHERE a.name = "name" AND a.namesafe = "namesafe"

如果您想使用OR：

SELECT a FROM Action a WHERE a.name = "name" OR a.namesafe = "namesafe"

Answer 4

你必须这样写：

SELECT a FROM Action a WHERE a.name = "name" AND a.namesafe = "namesafe"

Answer 5

为什么不使用AND？

SELECT a FROM Action a WHERE a.name = "name" AND a.namesafe = "namesafe"

Answer 6

你的意思是AND：

SELECT a FROM Action a WHERE a.name = "name" AND a.namesafe = "namesafe"

Answer 7

使用AND运算符，您可以加入以下两个条件：

SELECT a.*
FROM Action a 
WHERE a.name = 'name' AND 
      a.namesafe = 'namesafe'

Answer 8

使用AND运算符

SELECT a FROM Action a WHERE a.name =“name”AND a.namesafe =“namesafe

http://www.w3schools.com/sql/sql_and_or.asp

我可以在sql查询中两次使用where子句吗？

8 个答案: