Question

我试图在PowerBI中创建一个图表，显示两个日期之间每个给定时间内数据库中问题的平均天数。

CREATE TABLE Issues
(IssueID int,IssueName varchar(10),created datetime, closed datetime);

INSERT INTO Issues
VALUES
(1,'a','2012-01-01 00:00:00', '2012-05-01 00:00:00'),
(2,'b','2012-03-01 00:00:00', '2012-06-01 00:00:00');

我的第一个查询显示了数据库中的所有数据：

SELECT IssueID,
DATEDIFF(DAY,created,ISNULL(closed,GETDATE())) AS 'Days_Open'
FROM Issues

结果：

 IssueID    Days_Open
    1           4
    2           3

我想找到的是每天，当天开放的问题和平均天数开放？

DECLARE @StartDate DATETIME
DECLARE @EndDate DATETIME

SET @StartDate = '2012-01-01'
SET @EndDate = '2012-07-01'

例：问题每天开放

Date         IssueID    Days_Open
2012-01-01      1           0
2012-02-01      1           1
2012-03-01      1           2
2012-03-01      2           0
2012-04-01      1           3
2012-04-01      2           1
2012-05-01      1           4
2012-05-01      2           2
2012-06-01      2           3
Day 07 has no issues

平均

Date         Average_Days_Open
2012-01-01      0 (1 issue just created)
2012-02-01      1 (1 issue - 1 day old)
2012-03-01      1 (2 issues - (2+0)/2 = 1)
2012-04-01      2 (2 issues - (3+1)/2 = 2)
2012-05-01      3 (2 issues - (4+2)/2 = 3)
2012-06-01      3 (1 issue - (0+3)/1 = 3)
2012-07-01      0 (Since there were no issues that day)

如果我可以从两者获取数据，那么我应该能够在PowerBi中创建类似于此的折线图： Chart

有人可以帮忙吗？

Answer 1

基于语法我猜它是SQL Server：

1）查询：

WITH CTE_DatesTable
AS
(
  SELECT CAST('20120101' as datetime) AS [date]
  UNION ALL
  SELECT DATEADD(dd, 1, [date])
  FROM CTE_DatesTable
  WHERE DATEADD(dd, 1, [date]) <= '20120106'
)
SELECT [date] , i.IssueId,  DATEDIFF(DAY,i.created,d.[date]) AS Days_Open
FROM CTE_DatesTable d
JOIN Issues i
  ON d.date BETWEEN i.created AND i.closed
ORDER BY [date], IssueId
OPTION (MAXRECURSION 0);

<强> DBFiddle Demo

2）查询（平均）：

WITH CTE_DatesTable
AS
(
  SELECT CAST('20120101' as datetime) AS [date]
  UNION ALL
  SELECT DATEADD(dd, 1, [date])
  FROM CTE_DatesTable
  WHERE DATEADD(dd, 1, [date]) <= '20120106'
)
SELECT [date] ,AVG( DATEDIFF(DAY,i.created,d.[date]))
FROM CTE_DatesTable d
JOIN Issues i
  ON d.date BETWEEN i.created AND i.closed
GROUP BY [date]
ORDER BY [date]
OPTION (MAXRECURSION 0);

<强> DBFiddle Demo2

整个想法是生成日历表。

如果您需要超出范围的日期，可以使用LEFT JOIN：

WITH CTE_DatesTable
AS
(
  SELECT CAST('20120101' as datetime) AS [date]
  UNION ALL
  SELECT DATEADD(dd, 1, [date])
  FROM CTE_DatesTable
  WHERE DATEADD(dd, 1, [date]) <= '20120107'
)
SELECT [date] , COALESCE(AVG( DATEDIFF(DAY,i.created,d.[date])),0)
FROM CTE_DatesTable d
LEFT JOIN Issues i
  ON d.date BETWEEN i.created AND i.closed
GROUP BY [date]
ORDER BY [date]
OPTION (MAXRECURSION 0);

<强> DBFiddle Demo3

获取每天发布的平均天数（SQL）

1 个答案: