0
0

oracle 行转列和列转行的几种方式

1、准备数据：REST表

-- 创建表REST
CREATE TABLE REST (
  "ID" NUMBER,
  "AMOUNT" NUMBER(19,0),
  "MONTH" VARCHAR2(255 BYTE)
);

--执行添加数据语句
INSERT INTO "CERPAWCSADM"."REST" VALUES ('1', '100', 'Jan');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('1', '100', 'Feb');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('1', '66', 'Mar');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('1', '77', 'Jun');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('1', '88', 'Dec');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('1', '12', 'Aug');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('2', '22', 'Feb');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('2', '33', 'Apr');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('2', '232', 'Jul');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('2', '43', 'Sep');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('2', '544', 'Oct');
INSERT INTO "CERPAWCSADM"."REST" VALUES ('2', '65', 'Nov');

2、查询数据

3、行转列

方式1：使用 case when then方式

case 条件

when 值1 then 返回值1

when 值2 then 返回值2

..........

else 默认值

end

-- 使用case when 方式
SELECT
    id,
    sum( CASE month WHEN 'Jan' THEN amount ELSE 0 END ) AS Jan_amount,
    sum( CASE month WHEN 'Feb' THEN amount ELSE 0 END ) AS Feb_amount,
    sum( CASE month WHEN 'Mar' THEN amount ELSE 0 END ) AS Mar_amount,
    sum( CASE month WHEN 'Apr' THEN amount ELSE 0 END ) AS Apr_amount,
    sum( CASE month WHEN 'May' THEN amount ELSE 0 END ) AS May_amount,
    sum( CASE month WHEN 'Jun' THEN amount ELSE 0 END ) AS Jun_amount,
    sum( CASE month WHEN 'Jul' THEN amount ELSE 0 END ) AS Jul_amount,
    sum( CASE month WHEN 'Aug' THEN amount ELSE 0 END ) AS Aug_amount,
    sum( CASE month WHEN 'Sep' THEN amount ELSE 0 END ) AS Sep_amount,
    sum( CASE month WHEN 'Oct' THEN amount ELSE 0 END ) AS Oct_amount,
    sum( CASE month WHEN 'Nov' THEN amount ELSE 0 END ) AS Nov_amount,
    sum( CASE month WHEN 'Dec' THEN amount ELSE 0 END ) AS Dec_amount 
FROM
    REST 
GROUP BY
    id

case when 另一种方式：

    case when 条件 = 值1 then 返回值1 

    case when 条件 = 值1 then 返回值1 

    else 默认值

    end

    SELECT
    id,
    sum( CASE  WHEN month ='Jan' THEN amount ELSE 0 END ) AS Jan_amount,
    sum( CASE  WHEN month = 'Feb' THEN amount ELSE 0 END ) AS Feb_amount,
    sum( CASE  WHEN month = 'Mar' THEN amount ELSE 0 END ) AS Mar_amount,
    sum( CASE  WHEN month = 'Apr' THEN amount ELSE 0 END ) AS Apr_amount,
    sum( CASE  WHEN month = 'May' THEN amount ELSE 0 END ) AS May_amount,
    sum( CASE  WHEN month = 'Jun' THEN amount ELSE 0 END ) AS Jun_amount,
    sum( CASE  WHEN month = 'Jul' THEN amount ELSE 0 END ) AS Jul_amount,
    sum( CASE  WHEN month = 'Aug' THEN amount ELSE 0 END ) AS Aug_amount,
    sum( CASE  WHEN month = 'Sep' THEN amount ELSE 0 END ) AS Sep_amount,
    sum( CASE  WHEN month = 'Oct' THEN amount ELSE 0 END ) AS Oct_amount,
    sum( CASE  WHEN month = 'Nov' THEN amount ELSE 0 END ) AS Nov_amount,
    sum( CASE  WHEN month = 'Dec' THEN amount ELSE 0 END ) AS Dec_amount 
FROM
    REST 
GROUP BY
    id

结果为：

方式2： 使用 decode函数

decode函数： DECODE(条件, 值1, 返回值1, 值2,返回值2, 值3,返回值3, . . . else 缺省值)

含义：if 条件 = 值1 then 返回值1 elsif 条件 = 值2 then 返回值2 else (缺省值) endif

--    使用decode函数
SELECT
    id,
    sum( decode( month, 'Jan', amount, 0 ) ) Jan_amount,
    sum( decode( month, 'Feb', amount, 0 ) ) Feb_amount,
    sum( decode( month, 'Mar', amount, 0 ) ) Mar_amount,
    sum( decode( month, 'Apr', amount, 0 ) ) Apr_amount,
    sum( decode( month, 'May', amount, 0 ) ) May_amount,
    sum( decode( month, 'Jun', amount, 0 ) ) Jun_amount,
    sum( decode( month, 'Jul', amount, 0 ) ) Jul_amount,
    sum( decode( month, 'Aug', amount, 0 ) ) Aug_amount,
    sum( decode( month, 'Sep', amount, 0 ) ) Sep_amount,
    sum( decode( month, 'Oct', amount, 0 ) ) Oct_amount,
    sum( decode( month, 'Nov', amount, 0 ) ) Nov_amount,
    sum( decode( month, 'Dec', amount, 0 ) ) Dec_amount 
FROM
    REST 
GROUP BY
    id

结果和方式1一样

方式3：使用pivot函数

pivot
(
<聚合函数>(要聚合的列)
for <要转换的列> in (要转换的列值 as 要转换成的列名)
) 

SELECT
    * 
FROM
     REST pivot (
        SUM(amount) FOR month IN (
            'Jan' AS Jan_amount,
            'Feb' AS Feb_amount,
            'Mar' AS Mar_amount,
            'Apr' AS Apr_amount,
            'May' AS May_amount,
            'Jun' AS Jun_amount,
            'Jul' AS Jul_amount,
            'Aug' AS Aug_amount,
            'Sep' AS Sep_amount,
            'Oct' AS Oct_amount,
            'Nov' AS Nov_amount,
            'Dec' AS Dec_amount 
        ) 
    );

结果为：这个结果会发现，如果数据为空没有赋值为0

下面这个方法解决null 转为0 问题

SELECT
    NVl(Jan_amount,0) Jan_amount,
    NVl(Feb_amount,0) Feb_amount,
    NVl(Mar_amount,0) Mar_amount,
    NVl(Apr_amount,0) Apr_amount,
    NVl(May_amount,0) May_amount,
    NVl(Jun_amount,0) Jun_amount,
    NVl(Jul_amount,0) Jul_amount,
    NVl(Aug_amount,0) Aug_amount,
    NVl(Sep_amount,0) Sep_amount,
    NVl(Oct_amount,0) Oct_amount,
    NVl(Nov_amount,0) Nov_amount,
    NVl(Dec_amount,0) Dec_amount
FROM
     REST pivot (
        SUM(amount) FOR month IN (
            'Jan' AS Jan_amount,
            'Feb' AS Feb_amount,
            'Mar' AS Mar_amount,
            'Apr' AS Apr_amount,
            'May' AS May_amount,
            'Jun' AS Jun_amount,
            'Jul' AS Jul_amount,
            'Aug' AS Aug_amount,
            'Sep' AS Sep_amount,
            'Oct' AS Oct_amount,
            'Nov' AS Nov_amount,
            'Dec' AS Dec_amount 
        ) 
    );

结果和方式1一样：

4、列转行

在上述pivot 方法的原sql语句上再加上unpivot函数，将列再转为行，在unpivot函数中，amount：表示由列转换为行后的数据

month：表示由列转换为行后的列名

select * from REST
pivot (sum(amount) for month in (
            'Jan' AS Jan_amount,
            'Feb' AS Feb_amount,
            'Mar' AS Mar_amount,
            'Apr' AS Apr_amount,
            'May' AS May_amount,
            'Jun' AS Jun_amount,
            'Jul' AS Jul_amount,
            'Aug' AS Aug_amount,
            'Sep' AS Sep_amount,
            'Oct' AS Oct_amount,
            'Nov' AS Nov_amount,
            'Dec' AS Dec_amount 
))
unpivot ( amount for month in(Jan_amount,Feb_amount,Mar_amount,Apr_amount,May_amount,Jun_amount,Jul_amount,Aug_amount,Sep_amount,Oct_amount,Nov_amount,Dec_amount));

结果为：

5、直接使用unpivot函数 --列转行

准备数据：TEST表

CREATE TABLE TEST (
  "ID" NUMBER(12,0) NOT NULL,
  "JAN" VARCHAR2(255 BYTE),
  "FEB" VARCHAR2(255 BYTE),
  "MAR" VARCHAR2(255 BYTE),
  "APR" VARCHAR2(255 BYTE),
  "MAY" VARCHAR2(255 BYTE),
  "JUN" VARCHAR2(255 BYTE),
  "JUL" VARCHAR2(255 BYTE),
  "AUG" VARCHAR2(255 BYTE),
  "SEP" VARCHAR2(255 BYTE),
  "OCT" VARCHAR2(255 BYTE),
  "NOV" VARCHAR2(255 BYTE),
  "DEC" VARCHAR2(255 BYTE)
);
-- 插入数据
INSERT INTO "CERPAWCSADM"."TEST" VALUES ('1', '33', '2', '3', '4', '5', '6', '7', '8', '9', '99', '8', '6');
INSERT INTO "CERPAWCSADM"."TEST" VALUES ('2', '22', '3', '4', '6', '5', '7', '0', '7', '22', '21', '343', '76');
INSERT INTO "CERPAWCSADM"."TEST" VALUES ('3', '88', '3', '4', '5', '7', '9', '7', '2', '2', '231', '56', '78');

查询出的数据

列转行sql

SELECT
    * 
FROM TEST
    unpivot ( amount for month in(JAN,FEB,MAR,APR,MAY,JUN,JUL,AUG,SEP,OCT,NOV,DEC));

结果为：

标签： oracle 数据库 sql
本文转载自: https://blog.csdn.net/SUMMERENT/article/details/129562622
版权归原作者 SUMMERENT 所有， 如有侵权，请联系我们删除。
登录后发布评论

“oracle 行转列和列转行的几种方式”的评论:

还没有评论
关于作者
...
overfit同步小助手
文章同步
相关阅读

网络安全法-网络运行安全

使用selenium/drissionpage时如何阻止chrome自动跳转http到https

docker desktop 里部署的Open WebUI 管理员密码忘记了的处理方法

在ubuntu20.04中搭建onsite比赛运行环境

利用开源的低代码表单设计器FcDesigner高效管理和渲染复杂表单结构

Kafka学习笔记

【前端】浏览器输入url到页面呈现发生了什么？

文章导航