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  • mysql中文、英文别名排序问题,order by 关键字详解

     order by 关键字详解:

     
    SELECT
    intcode    AS 商品编码,
    product_title AS 名称,
    retailprice AS 零售价,
    purchaseprice AS 合同进价
    FROM product_detail
    WHERE brand='0063飘柔'
    AND purchaseprice>10
    ORDER BY purchaseprice DESC;
     
    desc是降序。升序关键字是ASC,如果不写desc和ASC,默认是升序排列的
     
     
     
     
    下面搞一搞中文别名排序:
    SELECT
    intcode    AS 商品编码,
    product_title AS 名称,
    retailprice AS 零售价,
    purchaseprice AS 合同进价
    FROM product_detail
    WHERE brand='0063飘柔'
    AND purchaseprice>10
    ORDER BY '零售价' DESC;
    本来想按照中文别名来排序,但是输出竟然是按照默认的升序。看来order by 语句出错了,就不执行了
     
     
     
     
    起个英文别名试试:
    SELECT
    intcode    AS 商品编码,
    product_title AS 名称,
    retailprice AS tt,
    purchaseprice AS 合同进价
    FROM product_detail
    WHERE brand='0063飘柔'
    AND purchaseprice>10
    ORDER BY tt DESC;
    竟然成功了。而且测试发现tt还不能加单引号。
     
     
     
    我靠,想想不对啊,我把中文别名也不加单引号试试。发现是我搞错了:
    SELECT
    intcode    AS 商品编码,
    product_title AS 名称,
    retailprice AS 零售价,
    purchaseprice AS 合同进价
    FROM product_detail
    WHERE brand='0063飘柔'
    AND purchaseprice>10
    ORDER BY 零售价 desc;
    ORDER BY 零售价 desc   语句中的零售价是中文,不加单引号,也能排序!!
     
     
    小结:(1)mysql对于执行顺序比较靠后的语句,如果出错了就不执行,而且不报错。
                (2)按照查询出来的字段的别名排序也是可以的,不管别名是中文还是英文,只要不加单引号就行。
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  • 原文地址:https://www.cnblogs.com/JohnTeslaaa/p/10542412.html
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