sqlserver通配符使用
欢迎进入Windows社区论坛,与300万技术人员互动交流 >>进入 SQL 通配符 在搜索数据库中的数据时,SQL 通配符可以替代一个或多个字符。 SQL 通配符必须与 LIKE 运算符一起使用,=操作是没有的。 通配符 描述 % 替代一个或多个字符 (相当于正则表达式中的 *
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SQL 通配符
在搜索数据库中的数据时,SQL 通配符可以替代一个或多个字符。
SQL 通配符必须与 LIKE 运算符一起使用,=操作是没有的。
通配符 | 描述 |
---|---|
% | 替代一个或多个字符(相当于正则表达式中的 * ) |
_ | 仅替代一个字符(相当于正则表达式中的 ? ) |
[charlist] | 字符列中的任何单一字符(事实上只有左方括号用于转义,右方括号使用最近优先原则匹配最近的左方括号) |
[^charlist] 或者 [!charlist] |
不在字符列中的任何单一字符用于排除一些字符进行匹配(这个与正则表达式中的一样) |
原始的表 (用在例子中的):
Persons 表:
Id | LastName | FirstName | Address | City |
---|---|---|---|---|
1 | Adams | John | Oxford Street | London |
2 | Bush | George | Fifth Avenue | New York |
3 | Carter | Thomas | Changan Street | Beijing |
使用 % 通配符
例子 1
现在,我们希望从上面的 "Persons" 表中选取居住在以 "Ne" 开始的城市里的人:
我们可以使用下面的 SELECT 语句:
SELECT * FROM Persons
WHERE City LIKE 'Ne%'
结果集:
Id | LastName | FirstName | Address | City |
---|---|---|---|---|
2 | Bush | George | Fifth Avenue | New York |
例子 2
接下来,我们希望从 "Persons" 表中选取居住在包含 "lond" 的城市里的人:
我们可以使用下面的 SELECT 语句:
SELECT * FROM Persons
WHERE City LIKE '%lond%'
结果集:
Id | LastName | FirstName | Address | City |
---|---|---|---|---|
1 | Adams | John | Oxford Street | London |
使用 _ 通配符
例子 1
现在,我们希望从上面的 "Persons" 表中选取名字的第一个字符之后是 "eorge" 的人:
我们可以使用下面的 SELECT 语句:
SELECT * FROM Persons
WHERE FirstName LIKE '_eorge'
结果集:
Id | LastName | FirstName | Address | City |
---|---|---|---|---|
2 | Bush | George | Fifth Avenue | New York |
例子 2
接下来,我们希望从 "Persons" 表中选取的这条记录的姓氏以 "C" 开头,然后是一个任意字符,然后是 "r",然后是任意字符,然后是 "er":
我们可以使用下面的 SELECT 语句:
SELECT * FROM Persons
WHERE LastName LIKE 'C_r_er'
结果集:
Id | LastName | FirstName | Address | City |
---|---|---|---|---|
3 | Carter | Thomas | Changan Street | Beijing |
使用 [charlist] 通配符
例子 1
现在,我们希望从上面的 "Persons" 表中选取居住的城市以 "A" 或 "L" 或 "N" 开头的人:
我们可以使用下面的 SELECT 语句:
SELECT * FROM Persons
WHERE City LIKE '[ALN]%'
结果集:
Id | LastName | FirstName | Address | City |
---|---|---|---|---|
1 | Adams | John | Oxford Street | London |
2 | Bush | George | Fifth Avenue | New York |
例子 2
现在,我们希望从上面的 "Persons" 表中选取居住的城市不以 "A" 或 "L" 或 "N" 开头的人:
我们可以使用下面的 SELECT 语句:
SELECT * FROM Persons
WHERE City LIKE '[!ALN]%'
结果集:
Id | LastName | FirstName | Address | City |
---|---|---|---|---|
3 | Carter | Thomas | Changan Street | Beijing |
通配符特殊用法:Escape
select 'asjldfj%%abc%asdfjklj'
select * from testhxj where name like '%/%abc/%%' escape '\'(这里\表示是通配符,这样匹配的数据是包含%abc%的数据,如果不用escape,就无法将%匹配为字符串)

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