SQL 行转列 列转行 PIVOT UNPIVOT

Posted 2020-10-08 biind

1.基础表

2.行转列，注意ISNULL函数的使用，在总成绩的统计中，ISNULL(-,0) 有必要使用

3.列转行，对列语文、数学、英语、政治，进行列转行，转为了2列，score scname 这两列，是新列，可以取名为 score11 scname22，随意

4.测试脚本

SELECT * FROM dbo.SC

--插入测试数据
INSERT dbo.SC        
SELECT NEWID(),\'001\',\'jack1\',\'数学\',88
UNION
SELECT NEWID(),\'002\',\'jack2\',\'语文\',55
UNION
SELECT NEWID(),\'003\',\'jack3\',\'英语\',66
UNION
SELECT NEWID(),\'004\',\'jack4\',\'政治\',77
--行转列
SELECT * FROM dbo.SC
PIVOT (SUM(Score) FOR SCName IN(语文,数学,英语,政治)) AS p

--列转行
SELECT * FROM (
    --这里是行转列
    SELECT sno,sname,ISNULL(语文,0) AS \'语文\',ISNULL(数学,0) AS \'数学\',ISNULL(英语,0) AS \'英语\',ISNULL(政治,0) AS \'政治\' FROM dbo.SC
    PIVOT (SUM(Score) FOR SCName IN(语文,数学,英语,政治)) AS p
) t
UNPIVOT (score FOR SCName IN(语文,数学,英语,政治)) AS up
WHERE score !=0

SELECT * FROM (
    --这里是行转列
    SELECT sno,sname,ISNULL(语文,0) AS \'语文\',ISNULL(数学,0) AS \'数学\',ISNULL(英语,0) AS \'英语\',ISNULL(政治,0) AS \'政治\' FROM dbo.SC
    PIVOT (SUM(Score) FOR SCName IN(语文,数学,英语,政治)) AS p
) t
UNPIVOT (Score11 FOR SCName22 IN(语文,数学,英语,政治)) AS up
WHERE Score11 !=0