• SQL 必知必会·笔记<3>过滤数据


    在同时使用ORDER BY 和WHERE 子句时,应该让ORDER BY 位于 WHERE 之后,否则将会产生错误

    WHERE子句操作符

    范围值检查

    使用BETWEEN 操作符,示例:

    SELECT prod_name, prod_price
    FROM Products
    WHERE prod_price BETWEEN 5 AND 10;

    2. 高级数据过滤

    组合WHERE子句

    AND操作符

    WHERE 子句中的关键字,用来指示检索满足所有给定条件的行:

    FROM Products
    WHERE vend_id = 'DLL01' AND prod_price <= 4;

     

    OR操作符

    WHERE子句中使用的关键字,用来表示检索匹配任一给定条件的行:

    SELECT prod_name, prod_price
    FROM Products
    WHERE vend_id = 'DLL01' OR vend_id = ‘BRS01’;

    IN操作符

    WHERE 子句中用来指定要匹配值的清单的关键字,功能与OR 相当:

    SELECT prod_name, prod_price
    FROM Products
    WHERE vend_id IN ( 'DLL01', 'BRS01' )
    ORDER BY prod_name;

    NOT操作符

    WHERE 子句中用来否定其后条件的关键字:

    SELECT prod_name
    FROM Products
    WHERE NOT vend_id = 'DLL01'
    ORDER BY prod_name;

      

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  • 原文地址:https://www.cnblogs.com/IPrograming/p/3269967.html
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