❶ 求幫助，sql統計某一狀態下的時間平均值
select a.*,datediff(ss,a.deCreateDatetime_datetime,b.deCreateDatetime_datetime)/2 as 時間差的平均值,
(select top 1 deCreateDatetime_datetime from myOrder_DE d where deType_nvarchar<>N'IR'
and d.deCreateDatetime_datetime>a.deCreateDatetime_datetime order by d.deCreateDatetime_datetime)
as IR下一個狀態的時間
from myOrder_DE a inner join myOrder_DE b
on a.deType_nvarchar=N'IR'
and a.deid_int<>(select max(deid_int) from myOrder_DE where deType_nvarchar=N'IR')
and b.deid_int=(select top 1 deid_int from myOrder_DE
where deid_int<(select top 1 deid_int from myOrder_DE c
where c.deType_nvarchar=N'IR' and c.deid_int>a.deid_int order by c.deid_int) order by deid_int desc)
order by b.deCreateDatetime_datetime
❷ 怎樣編寫SQL語句求平均成績
1、打開資料庫軟體，附加資料庫，右鍵選擇新建查詢。
❸ sql 求一列中某一時間段的平均值
select avg() from a where riqi between 20000115 and 20000123;
有問題歡迎繼續提問，請採納吧！
❹ 關於用sql語句求平均值，就是把一個表中的所有欄位按時間欄位的小時來求平均值，而不是按時間段求
--已出結果 SQLSERVER2000
--生成測試數據
CREATE TABLE TestA
(
a int,
b int,
c int,
time datetime
)
INSERT INTO TestA
SELECT 12,13,45,'2009-6-9 10:59:26'
UNION ALL
SELECT 11,41,43,'2009-6-9 10:59:30'
UNION ALL
SELECT 10,75,742,'2009-6-9 11:00:40'
UNION ALL
SELECT 78,72,56,'2009-6-9 11:30:50'
UNION ALL
SELECT 52,11,55,'2009-6-9 12:00:42'
UNION ALL
SELECT 11,41,43,'2009-6-9 12:59:30'
--查詢結果
SELECT A*1.0/FCount AS A平均值,B*1.0/FCount AS B平均值,C*1.0/FCount AS C平均值,Time
FROM(
SELECT SUM(a)AS A,SUM(b)AS B,SUM(c)AS C,
CONVERT(char(10),time,121)+' '+LTRIM(DATEPART(hour,time))+':00:00' AS Time,COUNT(*)AS FCount
FROM TestA
GROUP BY CONVERT(char(10),time,121),DATEPART(hour,time)
)AS T
--SELECT 1/2 =0 SELECT 1./2 =0.5 SELECT 1.0/2=0.5
❺ 獲取一個時刻開始60分鍾的，每分鍾數據的平均值sql怎麼寫，mysql的
函數UNIX_TIMESTAMP(createtime)把時間轉換成UNIX時間戳，也就是與1970年1月1日的秒數差，因為你是要求按每分鍾，所以DIV 60把秒轉換成分鍾，通過GROUP BY把數據分組，用AVG函數求出每個分組的平均值。
SELECT (UNIX_TIMESTAMP(createtime) DIV 60)
, AVG(stquantity) AS stquantity
, AVG(indoortemperature) AS indoortemperature
, AVG(indoorhumidity) AS indoorhumidity
, AVG(carbondioxide) AS carbondioxide
, AVG(voc) AS voc
FROM 表名
GROUP BY UNIX_TIMESTAMP(createtime) DIV 60
❻ SQL 按時間欄位每天分四個部分提取平均值
比如：
select case when convert(varchar(8),時間,108) between '00:00:00' and '05:59:59' then convert(varchar(10),時間,120) + '-1'
when convert(varchar(8),時間,108) between '06:00:00' and '11:59:59' then convert(varchar(10),時間,120) + '-2'
when convert(varchar(8),時間,108) between '12:00:00' and '17:59:59' then convert(varchar(10),時間,120) + '-3'
when convert(varchar(8),時間,108) between '18:00:00' and '23:59:59' then convert(varchar(10),時間,120) + '-4' end 時間段,
avg(值) 平均值
group by
case when convert(varchar(8),時間,108) between '00:00:00' and '05:59:59' then convert(varchar(10),時間,120) + '-1'
when convert(varchar(8),時間,108) between '06:00:00' and '11:59:59' then convert(varchar(10),時間,120) + '-2'
when convert(varchar(8),時間,108) between '12:00:00' and '17:59:59' then convert(varchar(10),時間,120) + '-3'
when convert(varchar(8),時間,108) between '18:00:00' and '23:59:59' then convert(varchar(10),時間,120) + '-4' end
❼ ACCESS SQL語句 指定日期間， 晝間(就是白天比如6:00--18:00)平均數據SQL怎麼寫
我模擬了你的數據。你要的結果是這樣的吧：
轉化為SQL語句則如下：
SELECTDateValue([時間])AS日期,Avg(數據)AS指定時間的平均值
FROM表4
WHERETimeValue([時間]) Between#6:0:0#And#18:0:0#
GROUPBYDateValue([時間]);
說明：datevalue()函數返回時間的「年月日」；timevalue()函數返回時間的「分時秒」。
❽ 怎麼用SQL求平均分
摘要 1:使用sql自帶的avg函數
❾ SQL計算平均分。
count()求和，avg()平均
❿ 如何用SQL求各分鍾內記錄的平均值
SELECT ID,convert(varchar(5),Time,120),avg(sum(speed)) from table_name
group by ID,convert(varchar(5),Time,120)
convert(varchar(5),Time,120) 看時間的前五個位元組 意思是到分為止
avg(sum(speed)) 把一分鍾內的速度加總 然後平均值