SQL Server - 示例时间序列

Question

在 PostgreSQL 中我们使用：

SELECT * FROM generate_series(1, 100)
SELECT * FROM generate_series('2020-01-01 00:00'::timestamp,'2020-01-02 00:00'::timestamp,'1 minutes')

我们如何在 Microsoft SQL Server 中创建时间序列？

Answer 1

您可以使用递归“翻译”T-SQL 中的语句：

DECLARE @datetime datetime2(0) = '2020-01-01 00:00:00'
DECLARE @start int = 1
DECLARE @stop int = 100

; WITH rCTE AS (
   SELECT @start - 1 AS rn 
   UNION ALL
   SELECT rn + 1 FROM rCTE WHERE rn < @stop
)
SELECT DATEADD(minute, rn, @datetime)
FROM rCTE
OPTION (MAXRECURSION 0)

Answer 2

SQL Server 没有“简单”功能。取而代之的是，杰夫·莫登（Jeff Moden）提出了很多想法，并支持计分表。又被其他人捡到了。

喜欢这个代码>

/*

Copyright Daniel Hutmacher under Creative Commons 4.0 license with attribution.
http://creativecommons.org/licenses/by/4.0/

Source: http://sqlsunday.com/downloads/

WHAT:       Returns a gregorian calendar table for a specific interval of dates.

DISCLAIMER: This script may not be suitable to run in a production
            environment. I cannot assume any responsibility regarding
            the accuracy of the output information, performance
            impacts on your server, or any other consequence. If
            your juristiction does not allow for this kind of
            waiver/disclaimer, or if you do not accept these terms,
            you are NOT allowed to store, distribute or use this
            code in any way.

USAGE:      @from: Starting date
            @to:   Ending date

VERSION:    2018-07-17

*/

ALTER FUNCTION Calendar.Dates(@from date, @to date)
RETURNS TABLE
AS

RETURN (
    --- Generic number table with 1000 rows:
    WITH n(i) AS (
        SELECT 0
        FROM        (VALUES (0), (1), (2), (3), (4), (5), (6), (7), (8), (9)) AS x1(i)
        CROSS APPLY (VALUES (0), (1), (2), (3), (4), (5), (6), (7), (8), (9)) AS x2(i)
        CROSS APPLY (VALUES (0), (1), (2), (3), (4), (5), (6), (7), (8), (9)) AS x3(i)),

    --- One row for each date between @from and @to.
    --- Uncomment x3 if you need more than 1 million days. :)
    n2(i) AS (
        SELECT TOP (DATEDIFF(day, @from, @to)+1)
               ROW_NUMBER() OVER (ORDER BY (SELECT NULL))-1
        FROM n AS x1, n AS x2 -- , n AS x3, n AS x4
        ),

    --- i is an incrementing integer, starting with 0 on @from.
    dt(i, [date]) AS(
        SELECT i, DATEADD(day, i, @from) AS [date]
        FROM n2)

    SELECT dt.i,
           dt.[date] AS [Date],
           CAST(YEAR(dt.[date]) AS smallint) AS [Year],
           CAST(DATEPART(quarter, dt.[date]) AS tinyint) AS [Quarter],
           CAST(CAST(YEAR(dt.[date]) AS char(4))+' Q'+CAST(DATEPART(quarter, dt.[date]) AS char(1)) AS char(7)) AS Year_quarter,
           CAST(MONTH(dt.[date]) AS tinyint) AS [Month],
           CAST(CAST(YEAR(dt.[date]) AS char(4))+'-'+REPLACE(STR(MONTH(dt.[date]), 2, 0), ' ', '0') AS char(7)) AS Year_month,
           CAST(DAY(dt.[date]) AS tinyint) AS [Day],
           CONVERT(char(10), dt.[date], 121) AS Date_ISO,

           CAST(dt1.iso_week_year AS smallint) AS ISO_week_year,
           CAST(DATEPART(isowk, dt.[date]) AS tinyint) AS [ISO_week],
           CAST(CAST(dt1.iso_week_year AS varchar(4))+' W'+REPLACE(STR(DATEPART(isowk, dt.[date]), 2, 0), ' ', '0') AS char(8)) AS ISO_year_week,
           CAST(dt1.weekday_iso AS tinyint) AS ISO_weekday_number,

           CAST(DATEPART(week, dt.[date]) AS tinyint) AS US_week,
           CAST(CAST(YEAR(dt.[date]) AS varchar(4))+' W'+REPLACE(STR(DATEPART(week, dt.[date]), 2, 0), ' ', '0') AS char(8)) AS US_year_week,
           CAST(dt1.weekday_us AS tinyint) AS US_weekday_number,

           DATENAME(weekday, dt.[date]) AS Weekday_name,
           CAST(DATEPART(dy, dt.[date]) AS smallint) AS Day_of_year,
           30*(MONTH(dt.[date])-1)+(CASE WHEN dt.[date]=EOMONTH(dt.[date]) THEN 30 ELSE DAY(dt.[date]) END) AS Day_of_year_30E_360
    FROM dt

    --- Calculation steps:
    CROSS APPLY (
        VALUES (
            1+(DATEPART(dw, dt.[date])+@@DATEFIRST-2)%7,
            1+(DATEPART(dw, dt.[date])+@@DATEFIRST-1)%7,
            YEAR(dt.[date])+(CASE WHEN DATEPART(isowk, dt.[date])>50 AND DATEPART(dy, dt.[date])<7 THEN -1
                                  WHEN DATEPART(isowk, dt.[date])=1  AND DATEPART(dy, dt.[date])>300 THEN 1
                                  ELSE 0 END)
        )) AS dt1(weekday_iso, weekday_us, iso_week_year)
    )

GO

它的核心是使用数字表来生成日期和其他属性。如果需要，这可以更改为时间。

Answer 3

这解决了为给定日期范围生成每分钟日期和时间的问题。最初的概念是十多年前由 Itzik Ben-Gan 提供的。它可以变成像@KnutBoehnert 那样的函数。详细信息在 cmets 中。 请注意，DATEADD 的日期部分数量限制为 INT 的正限制，对于这个问题，它是 2,147,483,647 分钟，当该数量的分钟被添加到 1900-01-01 00:00:00。

 DECLARE  @LoDT DATETIME2(0) = '2020-01-01 00:00' --Inclusive
         ,@HiDT DATETIME2(0) = '2020-01-02 00:00' --Inclusive
;
   WITH 
--====== Create up to 16 rows of one's as the initial row source for the Tally "Pseudo-Cursor" 
   E1(N) AS (SELECT 1 FROM (VALUES (1),(1),(1),(1),(1),(1),(1),(1),(1),(1),(1),(1),(1),(1),(1),(1))E0(N)),
--====== Create one numbered row per second in the desired date range starting at 0.
      -- I call this a "Pseudo-Cursor" because it's a "set based" way to count without using an explicit loop
      -- or a recursive CTE which is even slower and more resource intensive that a properly built WHILE loop.
Tally(N) AS (SELECT N = 0 UNION ALL               --Starts with "0"
             SELECT TOP(DATEDIFF(mi,@LoDT,@HiDT)) --Controls the number of minute rows to be created
                    N = ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) --Number of minutes to add to @LoDT for each row.
               FROM E1 a,E1 b,E1 c,E1 d,E1 e,E1 f,E1 g,E1 h) --Up to 16^8 or 4,294,967,296 rows thanks to CROSSJOIN.
            --===== Create the final date squence by adding the minute rows created above to @LoDT 
                 -- to create the date/time sequence.
             SELECT DateSeq = DATEADD(mi,t.N,@LoDT)
               FROM Tally t
              ORDER BY t.N
;