通配符

通配符与 SQL LIKE 运算符一起使用。SQL 通配符用于搜索表中的数据。

SQL 中的通配符是：％，_，[charlist]，[^ charlist]

％ - 零个或多个字符的替代

   Eg:  //selects all customers with a City starting with "Lo"
        SELECT * FROM Customers
        WHERE City LIKE 'Lo%';

       //selects all customers with a City containing the pattern "es"
      SELECT * FROM Customers
       WHERE City LIKE '%es%';

_ - 单个字符的替代品

Eg://selects all customers with a City starting with any character, followed by "erlin"
SELECT * FROM Customers
WHERE City LIKE '_erlin';

[charlist] - 要匹配的字符集和范围

Eg://selects all customers with a City starting with "a", "d", or "l"
SELECT * FROM Customers
WHERE City LIKE '[adl]%';

//selects all customers with a City starting with "a", "d", or "l"
SELECT * FROM Customers
WHERE City LIKE '[a-c]%';

[^ charlist] - 仅匹配括号内未指定的字符

Eg://selects all customers with a City starting with a character that is not "a", "p", or "l"
SELECT * FROM Customers
WHERE City LIKE '[^apl]%';

or

SELECT * FROM Customers
WHERE City NOT LIKE '[apl]%' and city like '_%';