SQL Server 一些查询技巧

--1.【行列转换】  
--列转行  
USE tempdb  
GO  
IF (OBJECT_ID('DEPT') IS NOT NULL)    
    DROP TABLE DEPT    
CREATE TABLE DEPT(NAME VARCHAR(5),COL1 INT,COL2 INT,COL3 INT,COL4 INT,COL5 INT,COL6 INT)    
  
INSERT INTO DEPT  
SELECT 'A',10,50,20,30,0,80  
UNION ALL  
SELECT 'B',50,20,10,10,20,40  
UNION ALL  
SELECT 'C',5,0,0,10,0,80  
  
SELECT * FROM DEPT  
  
select NAME,NEWCOLUMNS,value  
--into #TEMP   
from DEPT  
unpivot(  
    value for NEWCOLUMNS in(COL1,COL2,COL3,COL4,COL5,COL6)  
) as t  
/*  
NAME    NEWCOLUMNS  value  
A   COL1    10  
A   COL2    50  
A   COL3    20  
A   COL4    30  
A   COL5    0  
A   COL6    80  
B   COL1    50  
B   COL2    20  
B   COL3    10  
B   COL4    10  
B   COL5    20  
B   COL6    40  
C   COL1    5  
C   COL2    0  
C   COL3    0  
C   COL4    10  
C   COL5    0  
C   COL6    80  
*/  
  
--行转列  
select * from  #TEMP   
  
select * from #TEMP   
PIVOT(  
    max(value) for NEWCOLUMNS in(COL1,COL2,COL3,COL4,COL5,COL6)  
) as t   
/*  
NAME    COL1    COL2    COL3    COL4    COL5    COL6  
A   10  50  20  30  0   80  
B   50  20  10  10  20  40  
C   5   0   0   10  0   80  
*/  
  
--2.【每行中的数值统计：每行中各列数据的最大值、最小值、平均值】  
USE tempdb  
GO  
IF (OBJECT_ID('DEPT') IS NOT NULL)    
    DROP TABLE DEPT    
CREATE TABLE DEPT(NAME VARCHAR(5),COL1 INT,COL2 INT,COL3 INT,COL4 INT,COL5 INT,COL6 INT)    
  
INSERT INTO DEPT  
SELECT 'A',10,50,20,30,0,80  
UNION ALL  
SELECT 'B',50,20,10,10,20,40  
UNION ALL  
SELECT 'C',5,0,0,10,0,80  
  
  
SELECT *  
,MaxValue=(select MAX(COL) FROM (  
        SELECT COL1 AS COL  
        UNION ALL  
        SELECT COL2  
        UNION ALL  
        SELECT COL3   
        UNION ALL  
        SELECT COL4   
        UNION ALL  
        SELECT COL5   
        UNION ALL  
        SELECT COL6 ) A)  
,MINValue=(select MIN(COL) FROM (  
        SELECT COL1 AS COL  
        UNION ALL  
        SELECT COL2  
        UNION ALL  
        SELECT COL3   
        UNION ALL  
        SELECT COL4   
        UNION ALL  
        SELECT COL5   
        UNION ALL  
        SELECT COL6 ) B)  
,AVGValue=(select AVG(COL) FROM (  
        SELECT COL1 AS COL  
        UNION ALL  
        SELECT COL2  
        UNION ALL  
        SELECT COL3   
        UNION ALL  
        SELECT COL4   
        UNION ALL  
        SELECT COL5   
        UNION ALL  
        SELECT COL6 ) c)      
FROM DEPT  
  
/* 结果:  
NAME    COL1    COL2    COL3    COL4    COL5    COL6    MaxValue    MINValue    AVGValue  
A   10  50  20  30  0   80  80  0   31  
B   50  20  10  10  20  40  50  10  25  
C   5   0   0   10  0   80  80  0   15  
*/  
  
--3.【每列中的数值统计】  
USE tempdb  
GO  
IF (OBJECT_ID('DEPT') IS NOT NULL)    
    DROP TABLE DEPT    
CREATE TABLE DEPT(ID INT IDENTITY (1,1),VALUE INT)    
  
INSERT INTO DEPT(VALUE)  
VALUES(90),(86),(60),(80),(100),(0),(0),(85),(80),(65)  
  
SELECT * FROM DEPT  
  
select ID,VALUE  
,id = dense_rank() over(order by VALUE desc)  
,比例 = VALUE*100.0/sum(VALUE)OVER()  
,最大差值 =  max(VALUE)OVER() - VALUE  
,最小差值 =  VALUE - min(VALUE)OVER()   
from DEPT  
  
/*结果:  
ID  VALUE   id  比例  最大差值    最小差值  
5   100 1   15.479876160990 0   100  
1   90  2   13.931888544891 10  90  
2   86  3   13.312693498452 14  86  
8   85  4   13.157894736842 15  85  
9   80  5   12.383900928792 20  80  
4   80  5   12.383900928792 20  80  
10  65  6   10.061919504643 35  65  
3   60  7   9.287925696594  40  60  
6   0   8   0.000000000000  100 0  
7   0   8   0.000000000000  100 0  
*/  
  
--4.【某部门的所有上级机构或下级机构】  
IF (OBJECT_ID('DEPT') IS NOT NULL)    
    DROP TABLE DEPT    
CREATE TABLE DEPT(ID INT,PID INT, NAME VARCHAR(20))    
    
INSERT INTO DEPT VALUES    
(1,0,'总公司'),      
(2,1,'研发部'),    
(3,1,'销售部'),    
(4,1,'财务部'),      
(5,2,'研发一部'),    
(6,2,'研发二部'),    
(7,3,'销售一部'),    
(8,3,'销售二部'),    
(9,3,'销售三部'),  
(10,5,'小组A'),  
(11,5,'小组B')  
  
SELECT * FROM DEPT    
    
--求一个部门的所有下级，如[研发部] 的所有下级'   
--条件:所有部门的父id都等于[研发部]的ID,取到都是下级的   
;WITH D(ID,PID,NAME,LVL)    
AS(    
    SELECT ID,PID,NAME,0 LVL FROM DEPT WHERE NAME='研发部'     
    UNION ALL    
    SELECT DEPT.ID,DEPT.PID,DEPT.NAME,LVL +1      
    FROM DEPT INNER JOIN D ON DEPT.PID=D.ID  
)    
SELECT * FROM D    
    
--求一个部门的所有上级，如[研发一部] 的所有上级'    
;WITH D(ID,PID,NAME,LVL)    
AS(    
    SELECT ID,PID,NAME,0 LVL FROM DEPT WHERE NAME='研发一部'     
    UNION ALL    
    SELECT DEPT.ID,DEPT.PID,DEPT.NAME,LVL +1      
    FROM DEPT INNER JOIN D ON DEPT.ID=D.PID  
)    
SELECT * FROM D    
    
   
SELECT * FROM DEPT INNER JOIN (SELECT ID,PID,NAME FROM DEPT WHERE NAME='研发部' ) TAB ON DEPT.ID=TAB.ID  
  
  
--5.【添加 删除 更新 时取出数据】  
drop table #temp  
SELECT * FROM DEPT  --继续用上一步的表  
SELECT NAME into #temp FROM DEPT WHERE 1<>1  
  
SELECT * FROM #temp   
  
  
insert into #temp(NAME)  
output inserted.NAME    --into tableName(colName) 输出可插入到其他表  
SELECT NAME FROM DEPT   
  
Delete DEPT  
output deleted.NAME  
where PID = 3  
  
UPDATE #temp  
SET NAME = '集团'  
OUTPUT Inserted.NAME Old, Deleted.NAME New  
WHERE NAME = '总公司'   
  
  
  
--6.【Merge into】  
  
/*    
drop table #a;    
drop table #b;    
*/    
create table #a (aid int null,aname varchar(10) null);    
create table #b (bid int null,bname varchar(10) null);    
    
insert into #a values(1,'Value1');    
insert into #a values(3,'Value3');    
insert into #a values(4,'Value4');    
    
insert into #b values(1,'New Value1');    
insert into #b values(2,'New Value2');    
insert into #b values(3,'New Value3');    
    
merge into #a using #b     
on #a.aid=#b.bid  
when matched --and #a.aid = 1 （可增加条件）  
    then update set #a.aname=#b.bname   
when not matched  
    then insert values(#b.bid,#b.bname)    
when not matched by source then  
    delete; --必须分号结束  
    
    
select * from #a;    
select * from #b;    
  
  
  
--7.【多列查询同一值简化】  
  
select * from tableName  
where COL1=100 or COL2=100 or COL3=100 or COL4=100 or COL5=100 or COL6=100  
  
--简化操作  
select * from tableName where 100 in(COL1,COL2,COL3,COL4,COL5,COL6)  
  
  
  
--8.【同列字符相连】  
use tempdb  
go  
--  drop table tb  
create table tb(id int,value varchar(30))   
go  
insert into tb   
values  
(1,'aa'),   
(1,'bb'),   
(2,'aaa'),   
(2,'bbb'),   
(2,'ccc')   
  
select * from tb  
  
SELECT DISTINCT id,STUFF((SELECT ','+value FROM tb B WHERE A.id=B.id FOR XML PATH('')),1,1,'') AS value    
FROM tb A    
  
/*结果:  
id  value  
--- -----------  
1   aa,bb  
2   aaa,bbb,ccc  
*/  
  
--逆转换  
use tempdb  
go  
--  drop table tb  
create table tb(id int,value varchar(30))   
go  
insert into tb values(1,'aa,bb')   
insert into tb values(2,'aaa,bbb,ccc')   
  
select * from tb  
  
select A.id, B.value   
from(   
    select id, [value] = convert(xml,' <root> <v>' + replace([value], ',', ' </v> <v>') + ' </v> </root>') from tb   
)A   
outer apply(   
    select value = N.v.value('.', 'varchar(100)') from A.[value].nodes('/root/v') N(v)   
)B   
  
/*结果:  
id  value  
--  -----  
1   aa   
1   bb   
2   aaa   
2   bbb   
2   ccc   
*/  
  
--8.【同列数值分组累加】  
  
drop table #temp  
create table #temp(name varchar(1),value int)  
  
insert #temp  
select 'a',1 union all  
select 'b',5 union all  
select 'a',3 union all  
select 'a',5 union all  
select 'b',9 union all  
select 'b',5  
  
select * from #temp  
  
;with tabA as(  
    select row_number() over(partition by name order by name) id,name,value from #temp   
)  
, tabB AS(  
    select id,name,value,value as total from tabA WHERE id = 1  
    union all  
    select a.id,a.name,a.value,a.value+b.total   
    from tabA a inner join tabB b on a.name=b.name and a.id=b.id+1  
)    
select * from tabB order by name,id  
  
/*结果:  
id name value   total  
-- ---- -----   ----  
1   a   3       3  
2   a   5       8  
3   a   1       9  
1   b   5       5  
2   b   9       14  
3   b   5       19  
*/  
  
  
  
  
--【一条sql语句执行N次】  
CREATE TABLE TB(ID INT IDENTITY (1,1),NAME VARCHAR(40))    
  
INSERT INTO TB(NAME) SELECT 'KK'+CONVERT(VARCHAR(5),isnull(@@IDENTITY,0)+1)    
GO 10  
  
  
--【随机取出N条记录】  
select top 5 * from tableName order by newid()  

年内按月累计（如：2月累计为前两个月的，3月累计为前三个月的)

CREATE TABLE T (tDate DATETIME,tValue INT)
INSERT INTO dbo.T
	SELECT '2017-01-08',10 UNION
	SELECT '2017-01-25',20 UNION
	SELECT '2017-02-11',30 UNION
	SELECT '2017-02-28',40 UNION
	SELECT '2017-03-17',50 UNION
	SELECT '2017-04-03',60 UNION
	SELECT '2017-04-20',70 UNION
	SELECT '2017-05-07',80 UNION
	SELECT '2017-05-24',90
SELECT * FROM dbo.T;

SELECT MONTH(tDate) AS 月份,
(SELECT SUM(tValue) FROM dbo.T T1  WHERE MONTH(T1.tDate)<=MONTH(T.tDate)) 累计 
FROM dbo.T 
GROUP BY MONTH(tDate)

tDate                   tValue
----------------------- -----------
2017-01-08 00:00:00.000 10
2017-01-25 00:00:00.000 20
2017-02-11 00:00:00.000 30
2017-02-28 00:00:00.000 40
2017-03-17 00:00:00.000 50
2017-04-03 00:00:00.000 60
2017-04-20 00:00:00.000 70
2017-05-07 00:00:00.000 80
2017-05-24 00:00:00.000 90


(9 行受影响)


月份          累计
----------- -----------
1           30
2           100
3           150
4           280
5           450


(5 行受影响)

求x个月内产品逐月库存

if object_id('[huang]') is not null drop table [huang]
go 
create table [huang]([年] int,[月] int,[产品] varchar(1),[未出库数量] int)
insert [huang]
select 2013,11,'A',100 union all
select 2014,1,'A',300 union all
select 2013,10,'B',1000 union all
select 2013,11,'B',1500 union all
select 2013,12,'B',3001
--------------开始查询--------------------------
;WITH d AS 
(
 SELECT CONVERT(VARCHAR(10),DATEADD(mm,number,'2013-11-01'),120)[date],b.产品
 FROM master..spt_values cross JOIN (SELECT DISTINCT 产品 FROM [huang]) b
 WHERE [type]='p' AND number>0 AND number<7  --这个7可以控制月份
 
),cte AS (
select ISNULL([年],YEAR(d.[date])) [年],ISNULL([月],month(d.[date])) [月],ISNULL(a.[产品],d.产品) 产品,ISNULL([未出库数量],0)[未出库数量],ROW_NUMBER()OVER(PARTITION BY ISNULL(a.[产品],d.产品) ORDER BY ISNULL([年],YEAR(d.[date])),ISNULL([月],month(d.[date]))) id
 from [huang] a full JOIN d ON a.[年]=YEAR(d.[date]) AND a.[月]=MONTH(d.[date]) AND a.[产品]=d.产品
 ) 
 
 
 SELECT [年],[月],[产品],ISNULL((SELECT SUM([未出库数量]  ) FROM cte b WHERE a.id>b.id AND a.[产品]=b.[产品]),0)[未出库数量]
  FROM cte a 
 ORDER BY [产品],[年],a.月
 
 /*
 年           月           产品   未出库数量
----------- ----------- ---- -----------
2013        11          A    0
2013        12          A    100
2014        1           A    100
2014        2           A    400
2014        3           A    400
2014        4           A    400
2014        5           A    400
2013        10          B    0
2013        11          B    1000
2013        12          B    2500
2014        1           B    5501
2014        2           B    5501
2014        3           B    5501
2014        4           B    5501
2014        5           B    5501
 */