Average per quarter hour - sql

I have a table with these columns:
Id, Method, DateTime, time taken
Ex
1, Done, 2014-06-22 08:18:00.000, 2000
2, Not Done, 2014-06-23 04:15:00.000, 5000
3, Done, 2014-06-23 14:15:00.000, 6000
I want to have a result set as, "average time taken by DONE methods in each 15 min interval between 8AM to 15PM"
Please guide me on how to proceed on this, I am not sure if cursor fits in this req.

You can use a CTE to generate a list of quarters. Then left join to look up the run times per quarter. A group by will allow you to calculate the average.
In SQL Server 2012, the time type is available, and you can:
; with quarters as
(
select cast('08:00' as time) as time
union all
select dateadd(minute, 15, time)
from quarters
where time <= '14:30'
)
select q.time
, avg(rt.time_taken) as avg_time_taken
from quarters q
left join
RunTime rt
on q.time <= cast(rt.dt as time)
and cast(rt.dt as time) < dateadd(minute, 15, q.time)
and method = 'Done'
group by
q.time
Live example at SQL Fiddle.
For SQL Server 2008R2 and earler, you can use integer math instead:
; with quarters as
(
select 8*60 as min
union all
select min + 15
from quarters
where min < 15*60
)
select q.min / 60 as hour
, q.min % 60 as minute
, avg(rt.time_taken) as avg_time_taken
from quarters q
left join
(
select datepart(minute, dt) +
60 * datepart(hour, dt) as min
, time_taken
from RunTime
where method = 'Done'
) rt
on q.min <= rt.min and rt.min < q.min + 15
group by
q.min;
Live example at SQL Fiddle.

I'm not entirely sure if this is what you want, but here ist the code:
CREATE TABLE #Test(
id int IDENTITY(1,1) PRIMARY KEY,
Method nvarchar(50),
[Datetime] datetime,
timeTaken Bigint
)
CREATE TABLE #Result(
[Between] datetime,
[And] datetime,
[Avg] bigint)
INSERT INTO #Test (Method,Datetime,timeTaken)
VALUES(
'Done', '2014-06-22 08:18:00.000', 2000),
('Not Done', '2014-06-23 04:15:00.000', 5000),
('Done', '2014-06-23 14:15:00.000', 6000)
DECLARE #MaxTime datetime,#StartTime datetime,#Next datetime
SELECT #MaxTime = MAX([datetime]),
#StartTime = MIN([datetime])
FROM #TEST
WHILE #StartTime <= #MaxTime
BEGIN
SET #Next = (SELECT Dateadd(MINUTE,15,#StartTime))
INSERT INTO #Result
SELECT #StartTime AS [Between], #Next AS [And],AVG(timeTaken) AS [AVG]
FROM #Test
WHERE [Datetime] Between #StartTime AND #Next
AND Method = 'Done'
SET #StartTime = #Next
END
SELECT * FROM #Result
DROP TABLE #Test
DROP TABLE #Result
You can now set a where to the Select * from #result in which you can say between 8 AM and 3 PM
Please let me know if this is what you want
Etienne

Related

Script to populate timeslot table with 1-hour timeslots

I've table in my schema => TimeSlot, which has several attributes with id, start time, end time.
So the question is: how can you make a script that will make 23/24 records, for which starttime - endtime, for example, 0.00-1.00, 1.00-2.00, etc.
i've tried this with some example, but can not figure out how to code it(not even know if it is correct):
SET NOCOUNT ON
TRUNCATE TABLE TimeSlot
DECLARE #InitHour TIME(0) = '1'
DECLARE #FinitHour TIME(0) = '24'
WHILE #InitHour < #FinitHour
BEGIN
INSERT INTO TimeSlot(
TimeSlotID, StartTime, EndTime
)
SELECT
The simplest solution is to generate a sequence of numbers, you can do this using any table that has the required number of rows and use row_number for an arbitrary number sequence.
with seq as (
select top(24) Row_Number() over (order by (select null))-1 n
from sys.syscomments
)
insert into TimeSlot (StartTime, EndTime)
select Convert(time,Concat(n,':00')) StartTime,
DateAdd(hour, 1, Convert(time,Concat(n,':00'))) EndTime
from seq
The basic answer to your question is that you need to generate the results somehow. There are lots of methods. If you have a table lying around with at least 24 rows, then you can use that. A "native" SQL method uses a recursive CTE>
Then, the TimeSlotID should be generated automatically (typically as an identity column):
WITH CTE as (
SELECT convert(datetime, '01:00:00') as StartTime
UNION ALL
SELECT DATEADD(HOUR, 1, StartTime)
FROM CTE
WHERE StartTime < convert(datetime, '23:00:00')
)
INSERT INTO TimeSlot (StartTime, EndTime)
SELECT StartTime, DATEADD(HOUR, 1, StartTime)
FROM CTE;
Fiddle here: http://sqlfiddle.com/#!18/9bac2/12
Please, check this solution: http://sqlfiddle.com/#!18/4cb97/17
set nocount on
declare #hour int = 0
while #hour <= 23
begin
declare #time datetime =
convert(
datetime,
convert(varchar, #hour) + ':00:00'
)
insert into TimeSlot(StartTime, EndTime)
values(
#time, dateadd(hour, 1, #time)
)
set #hour = #hour + 1
end
select *
from TimeSlot

Get total working hours from SQL table

I have an attendance SQL table that stores the start and end day's punch of employee. Each punch (punch in and punch out) is in a separate record.
I want to calculate the total working hour of each employee for a requested month.
I tried to make a scalar function that takes two dates and employee ID and return the calculation of the above task, but it calculate only the difference of one date between all dates.
The data is like this:
000781 2015-08-14 08:37:00 AM EMPIN 539309898
000781 2015-08-14 08:09:48 PM EMPOUT 539309886
My code is:
#FromDate NVARCHAR(10)
,#ToDate NVARCHAR(10)
,#EmpID NVARCHAR(6)
CONVERT(NVARCHAR,DATEDIFF(HOUR
,(SELECT Time from PERS_Attendance att where attt.date between convert(date,#fromDate) AND CONVERT(Date,#toDate)
AND (EmpID= #EmpID OR ISNULL(#EmpID, '') = '') AND Funckey = 'EMPIN')
,(SELECT Time from PERS_Attendance att where attt.date between convert(date,#fromDate) AND CONVERT(Date,#toDate)
AND (EmpID= #EmpID OR ISNULL(#EmpID, '') = '') AND Funckey = 'EMPOUT') ))
FROM PERS_Attendance attt
One more approach that I think is simple and efficient.
It doesn't require modern functions like LEAD
it works correctly if the same person goes in and out several times during the same day
it works correctly if the person stays in over the midnight or even for several days in a row
it works correctly if the period when person is "in" overlaps the start OR end date-time.
it does assume that data is correct, i.e. each "in" is matched by "out", except possibly the last one.
Here is an illustration of a time-line. Note that start time happens when a person was "in" and end time also happens when a person was still "in":
All we need to do it calculate a plain sum of time differences between each event (both in and out) and start time, then do the same for end time. If event is in, the added duration should have a positive sign, if event is out, the added duration should have a negative sign. The final result is a difference between sum for end time and sum for start time.
summing for start:
|---| +
|----------| -
|-----------------| +
|--------------------------| -
|-------------------------------| +
--|====|--------|======|------|===|=====|---|==|---|===|====|----|=====|--- time
in out in out in start out in out in end out in out
summing for end:
|---| +
|-------| -
|----------| +
|--------------| -
|------------------------| +
|-------------------------------| -
|--------------------------------------| +
|-----------------------------------------------| -
|----------------------------------------------------| +
I would recommend to calculate durations in minutes and then divide result by 60 to get hours, but it really depends on your requirements. By the way, it is a bad idea to store dates as NVARCHAR.
DECLARE #StartDate datetime = '2015-08-01 00:00:00';
DECLARE #EndDate datetime = '2015-09-01 00:00:00';
DECLARE #EmpID nvarchar(6) = NULL;
WITH
CTE_Start
AS
(
SELECT
EmpID
,SUM(DATEDIFF(minute, (CAST(att.[date] AS datetime) + att.[Time]), #StartDate)
* CASE WHEN Funckey = 'EMPIN' THEN +1 ELSE -1 END) AS SumStart
FROM
PERS_Attendance AS att
WHERE
(EmpID = #EmpID OR #EmpID IS NULL)
AND att.[date] < #StartDate
GROUP BY EmpID
)
,CTE_End
AS
(
SELECT
EmpID
,SUM(DATEDIFF(minute, (CAST(att.[date] AS datetime) + att.[Time]), #StartDate)
* CASE WHEN Funckey = 'EMPIN' THEN +1 ELSE -1 END) AS SumEnd
FROM
PERS_Attendance AS att
WHERE
(EmpID = #EmpID OR #EmpID IS NULL)
AND att.[date] < #EndDate
GROUP BY EmpID
)
SELECT
CTE_End.EmpID
,(SumEnd - ISNULL(SumStart, 0)) / 60.0 AS SumHours
FROM
CTE_End
LEFT JOIN CTE_Start ON CTE_Start.EmpID = CTE_End.EmpID
OPTION(RECOMPILE);
There is LEFT JOIN between sums for end and start times, because there can be EmpID that has no records before the start time.
OPTION(RECOMPILE) is useful when you use Dynamic Search Conditions in T‑SQL. If #EmpID is NULL, you'll get results for all people, if it is not NULL, you'll get result just for one person.
If you need just one number (a grand total) for all people, then wrap the calculation in the last SELECT into SUM(). If you always want a grand total for all people, then remove #EmpID parameter altogether.
It would be a good idea to have an index on (EmpID,date).
My approach would be as follows:
CREATE FUNCTION [dbo].[MonthlyHoursByEmpID]
(
#StartDate Date,
#EndDate Date,
#Employee NVARCHAR(6)
)
RETURNS FLOAT
AS
BEGIN
DECLARE #TotalHours FLOAT
DECLARE #In TABLE ([Date] Date, [Time] Time)
DECLARE #Out TABLE ([Date] Date, [Time] Time)
INSERT INTO #In([Date], [Time])
SELECT [Date], [Time]
FROM PERS_Attendance
WHERE [EmpID] = #Employee AND [Funckey] = 'EMPIN' AND ([Date] > #StartDate AND [Date] < #EndDate)
INSERT INTO #Out([Date], [Time])
SELECT [Date], [Time]
FROM PERS_Attendance
WHERE [EmpID] = #Employee AND [Funckey] = 'EMPOUT' AND ([Date] > #StartDate AND [Date] < #EndDate)
SET #TotalHours = (SELECT SUM(CONVERT([float],datediff(minute,I.[Time], O.[Time]))/(60))
FROM #in I
INNER JOIN #Out O
ON I.[Date] = O.[Date])
RETURN #TotalHours
END
Assuming the entries are properly paired (in -> out -> in -> out -> in etc).
SQL Server 2012 and later:
DECLARE #Year int = 2015
DECLARE #Month int = 8
;WITH
cte AS (
SELECT EmpID,
InDate = LAG([Date], 1) OVER (PARTITION BY EmpID ORDER BY [Date]),
OutDate = [Date],
HoursWorked = DATEDIFF(hour, LAG([Date], 1) OVER (PARTITION BY EmpID ORDER BY [Date]), [Date]),
Funckey
FROM PERS_Attendance
)
SELECT EmpID,
TotalHours = SUM(HoursWorked)
FROM cte
WHERE Funckey = 'EMPOUT'
AND YEAR(InDate) = #Year
AND MONTH(InDate) = #Month
GROUP BY EmpID
SQL Server 2005 and later:
;WITH
cte1 AS (
SELECT *,
rn = ROW_NUMBER() OVER (PARTITION BY EmpID ORDER BY [Date])
FROM PERS_Attendance
),
cte2 AS (
SELECT a.EmpID, b.[Date] As InDate, a.[Date] AS OutDate,
HoursWorked = DATEDIFF(hour, b.[Date], a.[Date])
FROM cte1 a
LEFT JOIN cte1 b ON a.EmpID = b.EmpID and a.rn = b.rn + 1
WHERE a.Funckey = 'EMPOUT'
)
SELECT EmpID,
TotalHours = SUM(HoursWorked)
FROM cte2
WHERE YEAR(InDate) = #Year
AND MONTH(InDate) = #Month
GROUP BY EmpID

TSQL Averaging over datepart

I have a table with a datetime column in it, consider it an event log for simple, analogous purposes.
I want to produce a report detailing the average number of events that occur at each time of day, to 30 min accuracy.
so the logic is,
get just the time component of each date
round the time to the nearest 30 min window (it can be floored, i.e. 00:29 -> 00:00)
count these (grouped by date)
average all these counts over all days
I also don't want to have any time holes in my data, for example, if nothing occurred in the 00:00 - 00:30 range, i want to report a 0, rather than having a missing row.
How can I achieve this?
WITH TestDates (date) AS (
SELECT CONVERT(DATETIME, '2011-11-15 10:00') UNION ALL
SELECT CONVERT(DATETIME, '2011-11-15 11:31') UNION ALL
SELECT CONVERT(DATETIME, '2011-11-16 10:00')
-- CTE to generate 4 million rows with a sequential integer starting at 0
), GeneratedRows (seq) AS (
SELECT ROW_NUMBER() OVER (ORDER BY N1.number) - 1
FROM master..spt_values AS N1
CROSS JOIN master..spt_values AS N2
WHERE N1.name IS NULL
AND N2.name IS NULL
), RoundedTestDates (date) AS (
SELECT CASE
-- Subtract the minute part
WHEN DATEPART(MINUTE, date) < 25 THEN DATEADD(MINUTE, -1 * DATEPART(MINUTE, date), date)
-- Subtract the minute part, then add an hour
WHEN DATEPART(MINUTE, date) >= 45 THEN DATEADD(HOUR, 1, DATEADD(MINUTE, -1 * DATEPART(MINUTE, date), date))
-- Subtract the minute part, then add an half-hour
ELSE DATEADD(MINUTE, 30, DATEADD(MINUTE, -1 * DATEPART(MINUTE, date), date))
END
FROM TestDates
)
SELECT rounded_date = GeneratedPeriod.date
, ocurrences = COUNT(RoundedTestDates.date)
FROM (SELECT DATEADD(MINUTE, 30 * seq, (SELECT MIN(date) FROM RoundedTestDates))
FROM GeneratedRows
) AS GeneratedPeriod (date)
LEFT JOIN RoundedTestDates
ON GeneratedPeriod.date = RoundedTestDates.date
WHERE GeneratedPeriod.date <= (SELECT MAX(date) FROM RoundedTestDates)
GROUP BY GeneratedPeriod.date
ORDER BY 1
Here is the code you need: (tested in sql2008 and works fine!)
-- Table with the 48 30mins periods of the day
CREATE TABLE #Periods
(
Num INT
)
DECLARE #idt INT
SET #idt = 1
WHILE (#idt <= 48)
BEGIN
INSERT INTO #Periods VALUES (#idt)
SET #idt = #idt + 1
END
--Average of the count for each period on all days.
SELECT DayTable.Num, AVG(CAST(DayTable.DayCount AS DECIMAL))
FROM
( --Total incidents for each interval on each day.
SELECT CAST(FLOOR(CAST(#MyLog.LogDate AS FLOAT)) AS DATETIME) AS DayWithOutTime,
#Periods.Num AS Num,
COUNT(#MyLog.ID) AS DayCount
FROM #Periods LEFT JOIN #MyLog
ON #Periods.Num = (DATEPART(hh, #MyLog.LogDate)*60 + DATEPART(mi,#MyLog.LogDate))/30
GROUP BY CAST(FLOOR(CAST(#MyLog.LogDate AS FLOAT)) AS DATETIME),
#Periods.Num
) AS DayTable
GROUP BY DayTable.Num
DROP TABLE #Periods
Where #NyLog is the table where your datetime is. It shows the count of incidences for each 30min period. The Period 1 is 00:00 -> 00:30 and Period 48 is 23:30 -> 24:00.
In sybase sql is something like this, in sql-server you might need to do some changes but not much :)
create procedure Test #startDay varchar(8), #endDay varchar(8)
as
declare #ocurrence int
declare #numberOfDays int
select #numberOfDays = 0
create table #intervals (
interval_hour int,
interval_min_minute int,
interval_max_minute int,
ocurrences int
)
create table #insertions (
hour int,
minute int
)
declare #hour int, #minute int
select #hour = 0
-- create the intervals
while (#hour <> 24)
begin
insert into #intervals values(#hour,0,29,0)
insert into #intervals values(#hour,30,59,0)
select #hour = #hour + 1
end
while(#startDay <> #endDay)
begin
insert into #insertions
select datepart(hh, *yourcolumn*), datepart(mm, *yourcolumn*) from *yourdb..yourtable* where convert(varchar(8), *yourcolumn*, 112) = #startDay
select #startDay = convert(varchar(8), dateadd(dd, 1, convert(datetime, #startDay, 112)), 112)
select #numberOfDays = #numberOfDays + 1
end
declare cursor1 cursor for
select hour, minute from #insertions
open cursor1
fetch cursor1 into #hour, #minute
while (##sqlstatus=0)
begin
update #intervals
set i.ocurrences = i.ocurrences + 1
from #intervals i
where interval_hour = #hour and #minute between interval_min_minute and interval_max_minute
fetch cursor1 into #hour, #minute
end
close cursor1
select interval_hour 'hour', interval_min_minute 'min minute', interval_max_minute 'max minute', ocurrences,
case when ocurrences > 0 then convert(float, ocurrences) / convert(float, #numberOfDays) else 0 end 'ocurrences average' from #intervals
drop table #intervals
drop table #insertions
go
What I've done is use an auxiliary table of numbers (a 1 column table with number 1 to 1 million) and join to it, adding the value of the number with the dateadd function to the midnight of the date.
since you want 30 minute intervals, then you want to use the dateadd(minute, number*30, yourdate) where number <= 48 (since there are 1440 minutes in a day)/30 = 48 intervals. This will create your time intervals.
Then simply count your occurrences that happen in between the time intervals.

How can I generate a temporary table filled with dates in SQL Server 2000?

I need to make a temporary table that holds of range of dates, as well as a couple of columns that hold placeholder values (0) for future use. The dates I need are the first day of each month between $startDate and $endDate where these variables can be several years apart.
My original sql statement looked like this:
select dbo.FirstOfMonth(InsertDate) as Month, 0 as Trials, 0 as Sales
into #dates
from customer
group by dbo.FirstOfMonth(InsertDate)
"FirstOfMonth" is a user-defined function I made that pretty much does what it says, returning the first day of the month for the provided date with the time at exactly midnight.
This produced almost exactly what I needed until I discovered there were occasionally gaps in my dates where I had a few months were there were no records insert dates. Since my result must still have the missing months I need a different approach.
I have added the following declarations to the stored procedure anticipating their need for the range of the dates I need ...
declare $startDate set $startDate = select min(InsertDate) from customer
declare $endDate set $endDate = select max(InsertDate) from customer
... but I have no idea what to do from here.
I know this question is similar to this question but, quite frankly, that answer is over my head (I don't often work with SQL and when I do it tends to be on older versions of SQL Server) and there are a few minor differences that are throwing me off.
I needed something similar, but all DAYS instead of all MONTHS.
Using the code from MatBailie as a starting point, here's the SQL for creating a permanent table with all dates from 2000-01-01 to 2099-12-31:
CREATE TABLE _Dates (
d DATE,
PRIMARY KEY (d)
)
DECLARE #dIncr DATE = '2000-01-01'
DECLARE #dEnd DATE = '2100-01-01'
WHILE ( #dIncr < #dEnd )
BEGIN
INSERT INTO _Dates (d) VALUES( #dIncr )
SELECT #dIncr = DATEADD(DAY, 1, #dIncr )
END
This will quickly populate a table with 170 years worth of dates.
CREATE TABLE CalendarMonths (
date DATETIME,
PRIMARY KEY (date)
)
DECLARE
#basedate DATETIME,
#offset INT
SELECT
#basedate = '01 Jan 2000',
#offset = 1
WHILE (#offset < 2048)
BEGIN
INSERT INTO CalendarMonths SELECT DATEADD(MONTH, #offset, date) FROM CalendarMonths
SELECT #offset = #offset + #offset
END
You can then use it by LEFT joining on to that table, for the range of dates you require.
I would probably use a Calendar table. Create a permanent table in your database and fill it with all of the dates. Even if you covered a 100 year range, the table would still only have ~36,525 rows in it.
CREATE TABLE dbo.Calendar (
calendar_date DATETIME NOT NULL,
is_weekend BIT NOT NULL,
is_holiday BIT NOT NULL,
CONSTRAINT PK_Calendar PRIMARY KEY CLUSTERED (calendar_date)
)
Once the table is created, just populate it once in a loop, so that it's always out there and available to you.
Your query then could be something like this:
SELECT
C.calendar_date,
0 AS trials,
0 AS sales
FROM
dbo.Calendar C
WHERE
C.calendar_date BETWEEN #start_date AND #end_date AND
DAY(C.calendar_date) = 1
You can join in the Customers table however you need to, outer joining on FirstOfMonth(InsertDate) = C.calendar_date if that's what you want.
You can also include a column for day_of_month if you want which would avoid the overhead of calling the DAY() function, but that's fairly trivial, so it probably doesn't matter one way or another.
This of course will not work in SQL-Server 2000 but in a modern database where you don't want to create a permanent table. You can use a table variable instead creating a table so you can left join the data try this. Change the DAY to HOUR etc to change the increment type.
declare #CalendarMonths table (date DATETIME, PRIMARY KEY (date)
)
DECLARE
#basedate DATETIME,
#offset INT
SELECT
#basedate = '01 Jan 2014',
#offset = 1
INSERT INTO #CalendarMonths SELECT #basedate
WHILE ( DATEADD(DAY, #offset, #basedate) < CURRENT_TIMESTAMP)
BEGIN
INSERT INTO #CalendarMonths SELECT DATEADD(HOUR, #offset, date) FROM #CalendarMonths where DATEADD(DAY, #offset, date) < CURRENT_TIMESTAMP
SELECT #offset = #offset + #offset
END
A starting point of a useful kludge to specify a range or specific list of dates:
SELECT *
FROM
(SELECT CONVERT(DateTime,'2017-1-1')+number AS [Date]
FROM master..spt_values WHERE type='P' AND number<370) AS DatesList
WHERE DatesList.Date IN ('2017-1-1','2017-4-14','2017-4-17','2017-12-25','2017-12-26')
You can get 0 to 2047 out of master..spt_values WHERE type='P', so that's five and a half year's worth of dates if you need it!
Tested below and it works, though it's a bit convoluted.
I assigned arbitrary values to the dates for the test.
DECLARE #SD smalldatetime,
#ED smalldatetime,
#FD smalldatetime,
#LD smalldatetime,
#Mct int,
#currct int = 0
SET #SD = '1/15/2011'
SET #ED = '2/02/2012'
SET #FD = (DATEADD(dd, -1*(Datepart(dd, #SD)-1), #sd))
SET #LD = (DATEADD(dd, -1*(Datepart(dd, #ED)-1), #ED))
SET #Mct = DATEDIFF(mm, #FD, #LD)
CREATE TABLE #MyTempTable (FoM smalldatetime, Trials int, Sales money)
WHILE #currct <= #Mct
BEGIN
INSERT INTO #MyTempTable (FoM, Trials, Sales)
VALUES
(DATEADD(MM, #currct, #FD), 0, 0)
SET #currct = #currct + 1
END
SELECT * FROM #MyTempTable
DROP TABLE #MyTempTable
For SQL Server 2000, this stackoverflow post looks promising for a way to temporarily generate dates calculated off of a start and end date. It's not exactly the same but quite similar. This post has a very in-depth answer on truncating dates, if needed.
In case anyone stumbles on this question and is working in PostgreSQL instead of SQL Server 2000, here is how you might do it there...
PostgreSQL has a nifty series generating function. For your example, you could use this series of all days instead of generating an entire calendar table, and then do groupings and matchups from there.
SELECT current_date + s.a AS dates FROM generate_series(0,14,7) AS s(a);
dates
------------
2004-02-05
2004-02-12
2004-02-19
(3 rows)
SELECT * FROM generate_series('2008-03-01 00:00'::timestamp,
'2008-03-04 12:00', '10 hours');
generate_series
---------------------
2008-03-01 00:00:00
2008-03-01 10:00:00
2008-03-01 20:00:00
2008-03-02 06:00:00
2008-03-02 16:00:00
2008-03-03 02:00:00
2008-03-03 12:00:00
2008-03-03 22:00:00
2008-03-04 08:00:00
(9 rows)
I would also look into date_trunc from PostgreSQL using 'month' for the truncator field to maybe refactor your original query to easily match with a date_trunc version of the calendar series.
select top (datediff(D,#start,#end)) dateadd(D,id-1,#start)
from BIG_TABLE_WITH_NO_JUMPS_IN_ID
declare #start datetime
set #start = '2016-09-01'
declare #end datetime
set #end = '2016-09-30'
create table #Date
(
table_id int identity(1,1) NOT NULL,
counterDate datetime NULL
);
insert into #Date select top (datediff(D,#start,#end)) NULL from SOME_TABLE
update #Date set counterDate = dateadd(D,table_id - 1, #start)
The code above should populate the table with all the dates between the start and end. You would then just join on this table to get all of the dates needed. If you only needed a certain day of each month, you could dateadd a month instead.
SELECT P.Id
, DATEADD ( DD, -P.Id, P.Date ) AS Date
FROM (SELECT TOP 1000 ROW_NUMBER () OVER (ORDER BY (SELECT NULL)) AS Id, CAST(GETDATE () AS DATE) AS Date FROM master.dbo.spt_values) AS P
This query returns a table calendar for the last 1000 days or so. It can be put in a temporary or other table.
Create a table variable containing a date for each month in a year:
declare #months table (reportMonth date, PRIMARY KEY (reportMonth));
declare #start date = '2018', #month int = 0; -- base 0 month
while (#month < 12)
begin
insert into #months select dateAdd(month, #month, #start);
select #month = #month + 1;
end
--verify
select * from #months;
This is by far the quickest method I have found (much quicker than inserting rows 1 by 1 in a WHILE loop):
DECLARE #startDate DATE = '1900-01-01'
DECLARE #endDate DATE = '2050-01-01'
SELECT DATEADD(DAY, sequenceNumber, #startDate) AS TheDate
INTO #TheDates
FROM (
SELECT ones.n + 10*tens.n + 100*hundreds.n + 1000*thousands.n + 10000*tenthousands.n AS sequenceNumber
FROM
(VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) ones(n),
(VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) tens(n),
(VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) hundreds(n),
(VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) thousands(n),
(VALUES(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) tenthousands(n)
WHERE ones.n + 10*tens.n + 100*hundreds.n + 1000*thousands.n + 10000*tenthousands.n <= DATEDIFF(day, #startDate, #endDate)
) theNumbers
SELECT *
FROM #TheDates
ORDER BY TheDate
The recursive answer:
DECLARE #startDate AS date = '20220315';
DECLARE #endDate AS date = '20230316'; -- inclusive
WITH cte_minutes(dt)
AS (
SELECT
DATEFROMPARTS(YEAR(#startDate), MONTH(#startDate), 1)
UNION ALL
SELECT
DATEADD(month, 1, dt)
FROM
cte_minutes
WHERE DATEADD(month, 1, dt) < #endDate
)
SELECT
dt
into #dates
FROM
cte_minutes
WHERE
dt >= #startDate
AND
dt <= #endDate
OPTION (MAXRECURSION 2000);
DROP TABLE dbo.#dates

How I can select / sort dates by period intervals?

For ex:
If we have in table records like:
25/06/2009
28/12/2009
19/02/2010
16/04/2011
20/05/2012
I want to split/select this dates according to 6 month intervals starting from current date.
result should be like:
0-6 month from now: first record
7-12 month from now: second record
...
It will be much apreciated if you make this simple as I made it very stupid and complicated like:
declare variable like t1=curdate()+6
t2=curdate()+12
...
then selected records to fit between curdate() and t1, then t1 and t2 etc.
Thanks,
r.
CORRECTION: Had it backwards, Need to use Modulus, not integer division - sorry...
If MonthCount is a calculated value which counts the number of months since a specific Dec 31, and mod is modulus division (output the remainder after dividing)
Select [Column list here]
From Table
Group By Case When MonthCount Mod 12 < 6
Then 0 Else 1 End
In SQL Server, for example, you could use the DateDiff Function
Select [Column list here]
From Table
Group By Case When DateDiff(month, myDateColumn, curdate) % 12 < 6
Then 0 Else 1 End
( in SQL Server the percent sign is the modulus operator )
This will group all the record into buckets which each contain six months of data
SELECT (DATEDIFF(MONTH, thedate, GETDATE()) / 6) AS semester,
SUM(receipt)
FROM thetable
GROUP BY semester
ORDER BY semester
the key idea is grouping and ordering by the expression that gives you the "semester".
This question really baffled me, cos I couldn't actually come up with a simple solution for it. Damn.
Best I could manage was an absolute bastardization of the following where you create a Temp Table, insert the "Periods" into it, join back to your original table, and group off that.
Assume your content table has the following
ID int
Date DateTime
Counter int
And you're trying to sum all the counter's in six month periods
DECLARE #min_date datetime
select #min_date = min(date) from test
DECLARE #max_date datetime
select #max_date = max(date) from test
DECLARE #today_a datetime
DECLARE #today_b datetime
set #today_a = getdate()
set #today_b = getdate()
CREATE TABLE #temp (startdate DateTime, enddate DateTime)
WHILE #today_a > #min_date
BEGIN
INSERT INTO #temp (startDate, endDate) VALUES (dateadd(month, -6, #today_a), #today_a)
SET #today_a = dateadd(month, -6, #today_a)
END
WHILE #today_b < #max_date
BEGIN
INSERT INTO #temp (startDate, endDate) VALUES (#today_b, dateadd(month, 6, #today_b))
SET #today_b = dateadd(month, 6, #today_b)
END
SELECT * FROM #temp
SELECT
sum(counter),
'Between ' + Convert(nvarchar(10), startdate, 121) + ' => ' + Convert(nvarchar(10), enddate, 121) as Period
FROM test t
JOIN #Temp ht
ON t.Date between ht.startDate AND ht.EndDate
GROUP BY
'Between ' + Convert(nvarchar(10), startdate, 121) + ' => ' + Convert(nvarchar(10), enddate, 121)
DROP TABLE #temp
I really hope someone can come up with a better solution my brain has obviously melted.
Not quite what you're attempting to accomplish, but you could use the DATEDIFF function to distinguish the ranging of each record:
SELECT t.MonthGroup, SUM(t.Counter) AS TotalCount
FROM (
SELECT Counter, (DATEDIFF(m, GETDATE(), Date) / 6) AS MonthGroup
FROM Table
) t
GROUP BY t.MonthGroup
This would create a sub query with an expression that expresses the date ranging group you want. It would then group the sub-query by this date ranging group and you can then do whatever you want with the results.
Edit: I modified the example based on your example.
If you're using SQL Server:
SELECT *,
(
FLOOR
(
(
DATEDIFF(month, GETDATE(), date_column)
- CASE WHEN DAY(GETDATE()) > DAY(date_column) THEN 1 ELSE 0 END
) / 6.0
) * 6
) AS SixMonthlyInterval
FROM your_table
If you're using MySQL:
SELECT *,
(
FLOOR
(
(
((YEAR(date_column) - YEAR(CURDATE())) * 12)
+ MONTH(date_column) - MONTH(CURDATE())
- CASE WHEN DAY(CURDATE()) > DAY(date_column) THEN 1 ELSE 0 END
) / 6.0
) * 6
) AS SixMonthlyInterval
FROM your_table