Related
My query is as follows
SELECT
LEFT(TimePeriod,6) Period, -- string field with YYYYMMDD
SUM(Value) Value
FROM
f_Trans_GL
WHERE
Account = 228
GROUP BY
TimePeriod
And it returns
Period Value
---------------
201412 80
201501 20
201502 30
201506 50
201509 100
201509 100
I'd like to know the Value difference between rows where the period is 1 month apart. The calculation being [value period] - [value period-1].
The desired output being;
Period Value Calculated
-----------------------------------
201412 80 80 - null = 80
201501 20 20 - 80 = -60
201502 30 30 - 20 = 10
201506 50 50 - null = 50
201509 100 (100 + 100) - null = 200
This illustrates a second challenge, as the period needs to be evaluated if the year changes (the difference between 201501 and 201412 is one month).
And the third challenge being a duplicate Period (201509), in which case the sum of that period needs to be evaluated.
Any indicators on where to begin, if this is possible, would be great!
Thanks in advance
===============================
After I accepted the answer, I tailored this a little to suit my needs, the end result is:
WITH cte
AS (SELECT
ISNULL(CAST(TransactionID AS nvarchar), '_nullTransactionId_') + ISNULL(Description, '_nullDescription_') + CAST(Account AS nvarchar) + Category + Currency + Entity + Scenario AS UID,
LEFT(TimePeriod, 6) Period,
SUM(Value1) Value1,
CAST(LEFT(TimePeriod, 6) + '01' AS date) ord_date
FROM MyTestTable
GROUP BY LEFT(TimePeriod, 6),
TransactionID,
Description,
Account,
Category,
Currency,
Entity,
Scenario,
TimePeriod)
SELECT
a.UID,
a.Period,
--a.Value1,
ISNULL(a.Value1, 0) - ISNULL(b.Value1, 0) Periodic
FROM cte a
LEFT JOIN cte b
ON a.ord_date = DATEADD(MONTH, 1, b.ord_date)
ORDER BY a.UID
I have to get the new value (Periodic) for each UID. This UID must be determined as done here because the PK on the table won't work.
But the issue is that this will return many more rows than I actually have to begin with in my table. If I don't add a GROUP BY and ORDER by UID (as done above), I can tell that the first result for each combination of UID and Period is actually correct, the subsequent rows for that combination, are not.
I'm not sure where to look for a solution, my guess is that the UID is the issue here, and that it will somehow iterate over the field... any direction appreciated.
As pointed by other, first mistake is in Group by you need to Left(timeperiod, 6) instead of timeperiod.
For remaining calculation try something like this
;WITH cte
AS (SELECT LEFT(timeperiod, 6) Period,
Sum(value) Value,
Cast(LEFT(timeperiod, 6) + '01' AS DATE) ord_date
FROM f_trans_gl
WHERE account = 228
GROUP BY LEFT(timeperiod, 6))
SELECT a.period,
a.value,
a.value - Isnull(b.value, 0)
FROM cte a
LEFT JOIN cte b
ON a.ord_date = Dateadd(month, 1, b.ord_date)
If you are using SQL SERVER 2012 then this can be easily done using LAG analytic function
Using a derived table, you can join the data to itself to find rows that are in the preceding period. I have converted your Period to a Date value so you can use SQL Server's dateadd function to check for rows in the previous month:
;WITH cte AS
(
SELECT
LEFT(TimePeriod,6) Period, -- string field with YYYYMMDD
CAST(TimePeriod + '01' AS DATE) PeriodDate
SUM(Value) Value
FROM f_Trans_GL
WHERE Account = 228
GROUP BY LEFT(TimePeriod,6)
)
SELECT c1.Period,
c1.Value,
c1.Value - ISNULL(c2.Value,0) AS Calculation
FROM cte c1
LEFT JOIN cte c2
ON c1.PeriodDate = DATEADD(m,1,c2.PeriodDate)
Without cte, you can also try something like this
SELECT A.Period,A.Value,A.Value-ISNULL(B.Value) Calculated
FROM
(
SELECT LEFT(TimePeriod,6) Period
DATEADD(M,-1,(CONVERT(date,LEFT(TimePeriod,6)+'01'))) PeriodDatePrev,SUM(Value) Value
FROM f_Trans_GL
WHERE Account = 228
GROUP BY LEFT(TimePeriod,6)
) AS A
LEFT OUTER JOIN
(
SELECT LEFT(TimePeriod,6) Period
(CONVERT(date,LEFT(TimePeriod,6)+'01')) PeriodDate,SUM(Value) Value
FROM f_Trans_GL
WHERE Account = 228
GROUP BY LEFT(TimePeriod,6)
) AS B
ON (A.PeriodDatePrev = B.PeriodDate)
ORDER BY 1
Given a table structured like that:
id | news_id(fkey)| status | date
1 10 PUBLISHED 2016-01-10
2 20 UNPUBLISHED 2016-01-10
3 10 UNPUBLISHED 2016-01-12
4 10 PUBLISHED 2016-01-15
5 10 UNPUBLISHED 2016-01-16
6 20 PUBLISHED 2016-01-18
7 10 PUBLISHED 2016-01-18
8 20 UNPUBLISHED 2016-01-20
9 30 PUBLISHED 2016-01-20
10 30 UNPUBLISHED 2016-01-21
I'd like to count distinct news that, in given period time, had first and last status equal(and also status equal to given in query)
So, for this table query from 2016-01-01 to 2016-02-01 would return:
1 (with WHERE status = 'PUBLISHED') because news_id 10 had PUBLISHED in both first( 2016-01-10 ) and last row (2016-01-18)
1 (with WHERE status = 'UNPUBLISHED' because news_id 20 had UNPUBLISHED in both first and last row
notice how news_id = 30 does not appear in results, as his first/last statuses were contrary.
I have done that using following query:
SELECT count(*) FROM
(
SELECT DISTINCT ON (news_id)
news_id, status as first_status
FROM news_events
where date >= '2015-11-12 15:01:56.195'
ORDER BY news_id, date
) first
JOIN (
SELECT DISTINCT ON (news_id)
news_id, status as last_status
FROM news_events
where date >= '2015-11-12 15:01:56.195'
ORDER BY news_id, date DESC
) last
using (news_id)
where first_status = last_status
and first_status = 'PUBLISHED'
Now, I have to transform query into SQL our internal Java framework, unfortunately it does not support subqueries, except when using EXISTS or NOT EXISTS. I was told to transform the query to one using EXISTS clause(if it is possible) or try finding another solution. I am, however, clueless. Could anyone help me do that?
edit: As I am being told right now, the problem lies not with our framework, but in Hibernate - if I understood correctly, "you cannot join an inner select in HQL" (?)
Not sure if this adresses you problem correctly, since it is more of a workaround. But considering the following:
News need to be published before they can be "unpublished". So if you'd add 1 for each "published" and substract 1 for each "unpublished" your balance will be positive (or 1 to be exact) if first and last is "published". It will be 0 if you have as many unpublished as published and negative, if it has more unpublished than published (which logically cannot be the case but obviously might arise, since you set a date threshhold in the query where a 'published' might be occured before).
You might use this query to find out:
SELECT SUM(CASE status WHEN 'PUBLISHED' THEN 1 ELSE -1 END) AS 'publishbalance'
FROM news_events
WHERE date >= '2015-11-12 15:01:56.195'
GROUP BY news_id
First of all, subqueries are a substantial part of SQL. A framework forbidding their use is a bad framework.
However, "first" and "last" can be expressed with NOT EXISTS: where not exists an earlier or later entry for the same news_id and date range.
select count(*)
from mytable first
join mytable last on last.news_id = first.news_id
where date between #from and #to
and not exists
(
select *
from mytable before_first
where before_first.news_id = first.news_id
and before_first.date < first.date
and before_first.date >= #from
)
and not exists
(
select *
from mytable after_last
where after_last.news_id = last.news_id
and after_last.date > last.date
and after_last.date <= #to
)
and first.status = #status
and last.status = #status;
NOT EXISTS to the rescue:
SELECT ff.id ,ff.news_id ,ff.status , ff.zdate AS startdate
, ll.zdate AS enddate
FROM newsflash ff
JOIN newsflash ll
ON ff.news_id = ll.news_id
AND ff.status = ll.status
AND ff.zdate < ll.zdate
AND NOT EXISTS (
SELECT * FROM newsflash nx
WHERE nx.news_id = ff.news_id
AND nx.zdate >= '2016-01-01' AND nx.zdate < '2016-02-01'
AND (nx.zdate < ff.zdate OR nx.zdate > ll.zdate)
)
ORDER BY ff.id
;
I want to get all times that an event is not taking place for each room. The start of the day is 9:00:00 and end is 22:00:00.
What my database looks like is this:
Event EventStart EventEnd Days Rooms DayStarts
CISC 3660 09:00:00 12:30:00 Monday 7-3 9/19/2014
MATH 2501 15:00:00 17:00:00 Monday:Wednesday 7-2 10/13/2014
CISC 1110 14:00:00 16:00:00 Monday 7-3 9/19/2014
I want to get the times that aren't in the database.
ex. For SelectedDate (9/19/2014) the table should return:
Room FreeTimeStart FreeTimeEnd
7-3 12:30:00 14:00:00
7-3 16:00:00 22:00:00
ex2. SelectedDate (10/13/2014):
Room FreeTimeStart FreeTimeEnd
7-2 9:00:00 15:00:00
7-2 17:00:00 22:00:00
What I have tried is something like this:
select * from Events where ________ NOT BETWEEN eventstart AND eventend;
But I do not know what to put in the place of the space.
This was a pretty complex request. SQL works best with sets, and not looking at line by line. Here is what I came up with. To make it easier to figure out, I wrote it as a series of CTE's so I could work through the problem a step at a time. I am not saying that this is the best possible way to do it, but it doesn't require the use of any cursors. You need the Events table and a table of the room names (otherwise, you don't see a room that doesn't have any bookings).
Here is the query and I will explain the methodology.
DECLARE #Events TABLE (Event varchar(20), EventStart Time, EventEnd Time, Days varchar(50), Rooms varchar(10), DayStarts date)
INSERT INTO #Events
SELECT 'CISC 3660', '09:00:00', '12:30:00', 'Monday', '7-3', '9/19/2014' UNION
SELECT 'MATH 2501', '15:00:00', '17:00:00', 'Monday:Wednesday', '7-2', '10/13/2014' UNION
SELECT 'CISC 1110', '14:00:00', '16:00:00', 'Monday', '7-3', '9/19/2014'
DECLARE #Rooms TABLE (RoomName varchar(10))
INSERT INTO #Rooms
SELECT '7-2' UNION
SELECT '7-3'
DECLARE #SelectedDate date = '9/19/2014'
DECLARE #MinTimeInterval int = 30 --smallest time unit room can be reserved for
;WITH
D1(N) AS (
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
),
D2(N) AS (SELECT 1 FROM D1 a, D1 b),
D4(N) AS (SELECT 1 FROM D2 a, D2 b),
Numbers AS (SELECT TOP 3600 ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) -1 AS Number FROM D4),
AllTimes AS
(SELECT CAST(DATEADD(n,Numbers.Number*#MinTimeInterval,'09:00:00') as time) AS m FROM Numbers
WHERE DATEADD(n,Numbers.Number*#MinTimeInterval,'09:00:00') <= '22:00:00'),
OccupiedTimes AS (
SELECT e.Rooms, ValidTimes.m
FROM #Events E
CROSS APPLY (SELECT m FROM AllTimes WHERE m BETWEEN CASE WHEN e.EventStart = '09:00:00' THEN e.EventStart ELSE DATEADD(n,1,e.EventStart) END and CASE WHEN e.EventEnd = '22:00:00' THEN e.EventEnd ELSE DATEADD(n,-1,e.EventEnd) END) ValidTimes
WHERE e.DayStarts = #SelectedDate
),
AllRoomsAllTimes AS (
SELECT * FROM #Rooms R CROSS JOIN AllTimes
), AllOpenTimes AS (
SELECT a.*, ROW_NUMBER() OVER( PARTITION BY (a.RoomName) ORDER BY a.m) AS pos
FROM AllRoomsAllTimes A
LEFT OUTER JOIN OccupiedTimes o ON a.RoomName = o.Rooms AND a.m = o.m
WHERE o.m IS NULL
), Finalize AS (
SELECT a1.RoomName,
CASE WHEN a3.m IS NULL OR DATEDIFF(n,a3.m, a1.m) > #MinTimeInterval THEN a1.m else NULL END AS FreeTimeStart,
CASE WHEN a2.m IS NULL OR DATEDIFF(n,a1.m,a2.m) > #MinTimeInterval THEN A1.m ELSE NULL END AS FreeTimeEnd,
ROW_NUMBER() OVER( ORDER BY a1.RoomName ) AS Pos
FROM AllOpenTimes A1
LEFT OUTER JOIN AllOpenTimes A2 ON a1.RoomName = a2.RoomName and a1.pos = a2.pos-1
LEFT OUTER JOIN AllOpenTimes A3 ON a1.RoomName = a3.RoomName and a1.pos = a3.pos+1
WHERE A2.m IS NULL OR DATEDIFF(n,a1.m,a2.m) > #MinTimeInterval
OR
A3.m IS NULL OR DATEDIFF(n,a3.m, a1.m) > #MinTimeInterval
)
SELECT F1.RoomName, f1.FreeTimeStart, f2.FreeTimeEnd FROM Finalize F1
LEFT OUTER JOIN Finalize F2 ON F1.Pos = F2.pos-1 AND f1.RoomName = f2.RoomName
WHERE f1.pos % 2 = 1
In the first several lines, I create temp variables to simulate your tables Events and Rooms.
The variable #MinTimeInterval determines what time interval the room schedules can be on (every 30 min, 15 min, etc - this number needs to divide evenly into 60).
Since SQL cannot query data that is missing, we need to create a table that holds all of the times that we want to check for. The first several lines in the WITH create a table called AllTimes which are all the possible time intervals in your day.
Next, we get a list of all of the times that are occupied (OccupiedTimes), and then LEFT OUTER JOIN this table to the AllTimes table which gives us all the available times. Since we only want the start and end of each free time, create the Finalize table which self joins each record to the previous and next record in the table. If the times in these rows are greater than #MinTimeInterval, then we know it is either a start or end of a free time.
Finally we self join this last table to put the start and end times in the same row and only look at every other row.
This will need to be adjusted if a single row in Events spans multiple days or multiple rooms.
Here's a solution that will return the "complete picture" including rooms that aren't booked at all for the day in question:
Declare #Date char(8) = '20141013'
;
WITH cte as
(
SELECT *
FROM -- use your table name instead of the VALUES construct
(VALUES
('09:00:00','12:30:00' ,'7-3', '20140919'),
('15:00:00','17:00:00' ,'7-2', '20141013'),
('14:00:00','16:00:00' ,'7-3', '20140919')) x(EventStart , EventEnd,Rooms, DayStarts)
), cte_Days_Rooms AS
-- get a cartesian product for the day specified and all rooms as well as the start and end time to compare against
(
SELECT y.EventStart,y.EventEnd, x.rooms,a.DayStarts FROM
(SELECT #Date DayStarts) a
CROSS JOIN
(SELECT DISTINCT Rooms FROM cte)x
CROSS JOIN
(SELECT '09:00:00' EventStart,'09:00:00' EventEnd UNION ALL
SELECT '22:00:00' EventStart,'22:00:00' EventEnd) y
), cte_1 AS
-- Merge the original data an the "base data"
(
SELECT * FROM cte WHERE DayStarts=#Date
UNION ALL
SELECT * FROM cte_Days_Rooms
), cte_2 as
-- use the ROW_NUMBER() approach to sort the data
(
SELECT *, ROW_NUMBER() OVER(PARTITION BY DayStarts, Rooms ORDER BY EventStart) as pos
FROM cte_1
)
-- final query: self join with an offest of one row, eliminating duplicate rows if a room is booked starting 9:00 or ending 22:00
SELECT c2a.DayStarts, c2a.Rooms , c2a.EventEnd, c2b.EventStart
FROM cte_2 c2a
INNER JOIN cte_2 c2b on c2a.DayStarts = c2b.DayStarts AND c2a.Rooms =c2b.Rooms AND c2a.pos = c2b.pos -1
WHERE c2a.EventEnd <> c2b.EventStart
ORDER BY c2a.DayStarts, c2a.Rooms
I have a table like this.
_id (integer)
event_name(varchar(20))
event_date(timestamp)
Here is some sample data given below.
ID event_date event_name
101 2013-04-24 18:33:37.694818 event_A
102 2013-04-24 20:34:37.000000 event_B
103 2013-04-24 20:40:37.000000 event_A
104 2013-04-25 01:00:00.694818 event_B
105 2013-04-25 12:00:15.694818 event_A
I need the data from above table in below format.
Date count_eventA count_eventB
2013-04-24 2 1
2013-04-25 1 1
hence basically in need the count of each event on each date.
I have tried below query for getting the desired result.
SELECT A.date1 AS Date ,
A.count1 AS count_eventA,
B.count2 AS count_eventB,
FROM
(SELECT count(event_name)AS count1,
event_date::date AS date1
FROM tblname
WHERE event_name='event_A'
GROUP BY (event_date::date))AS A
LEFT JOIN
(SELECT count(event_name)AS count1,
event_date::date AS date1
FROM tblname
WHERE event_name='event_B'
GROUP BY (event_date::date))AS B ON A.date1=B.date2
Can someone please suggest me to find out a better and optimized query? , or I am following a good approach .
Something on this lines should work:
select event_date::date AS Date ,
count_eventA = sum(case when event_name = 'event_A' then 1 else 0 end),
count_eventB = sum(case when event_name = 'event_B' then 1 else 0 end)
from tblname
GROUP BY (event_date::date))
If you have more events you only need to add more sum(case) lines :)
The DBEngine only runs through the table once to give you the totals, independiently of the number of the events you want to count: when you have a high rowcount you will observe significant delay with the original query. Should I add this to my answer, you think
Simpler (and cleaner) than the case syntax:
select
event_date::date as Date,
count(event_name = 'event_A' or null) count_eventA,
count(event_name = 'event_B' or null) count_eventB
from t
group by 1
you are looking for PIVOT and UNPIVOT in sql check below example is very handy
http://blog.sqlauthority.com/2008/06/07/sql-server-pivot-and-unpivot-table-examples/
For a development aid project I am helping a small town in Nicaragua improving their water-network-administration.
There are about 150 households and every month a person checks the meter and charges the houshold according to the consumed water (reading from this month minus reading from last month). Today all is done on paper and I would like to digitalize the administration to avoid calculation-errors.
I have an MS Access Table in mind - e.g.:
*HousholdID* *Date* *Meter*
0 1/1/2013 100
1 1/1/2013 130
0 1/2/2013 120
1 1/2/2013 140
...
From this data I would like to create a query that calculates the consumed water (the meter-difference of one household between two months)
*HouseholdID* *Date* *Consumption*
0 1/2/2013 20
1 1/2/2013 10
...
Please, how would I approach this problem?
This query returns every date with previous date, even if there are missing months:
SELECT TabPrev.*, Tab.Meter as PrevMeter, TabPrev.Meter-Tab.Meter as Diff
FROM (
SELECT
Tab.HousholdID,
Tab.Data,
Max(Tab_1.Data) AS PrevData,
Tab.Meter
FROM
Tab INNER JOIN Tab AS Tab_1 ON Tab.HousholdID = Tab_1.HousholdID
AND Tab.Data > Tab_1.Data
GROUP BY Tab.HousholdID, Tab.Data, Tab.Meter) As TabPrev
INNER JOIN Tab
ON TabPrev.HousholdID = Tab.HousholdID
AND TabPrev.PrevData=Tab.Data
Here's the result:
HousholdID Data PrevData Meter PrevMeter Diff
----------------------------------------------------------
0 01/02/2013 01/01/2013 120 100 20
1 01/02/2013 01/01/2012 140 130 10
The query above will return every delta, for every households, for every month (or for every interval). If you are just interested in the last delta, you could use this query:
SELECT
MaxTab.*,
TabCurr.Meter as CurrMeter,
TabPrev.Meter as PrevMeter,
TabCurr.Meter-TabPrev.Meter as Diff
FROM ((
SELECT
Tab.HousholdID,
Max(Tab.Data) AS CurrData,
Max(Tab_1.Data) AS PrevData
FROM
Tab INNER JOIN Tab AS Tab_1
ON Tab.HousholdID = Tab_1.HousholdID
AND Tab.Data > Tab_1.Data
GROUP BY Tab.HousholdID) As MaxTab
INNER JOIN Tab TabPrev
ON TabPrev.HousholdID = MaxTab.HousholdID
AND TabPrev.Data=MaxTab.PrevData)
INNER JOIN Tab TabCurr
ON TabCurr.HousholdID = MaxTab.HousholdID
AND TabCurr.Data=MaxTab.CurrData
and (depending on what you are after) you could only filter current month:
WHERE
DateSerial(Year(CurrData), Month(CurrData), 1)=
DateSerial(Year(DATE()), Month(DATE()), 1)
this way if you miss a check for a particular household, it won't show.
Or you might be interested in showing last month present in the table (which can be different than current month):
WHERE
DateSerial(Year(CurrData), Month(CurrData), 1)=
(SELECT MAX(DateSerial(Year(Data), Month(Data), 1))
FROM Tab)
(here I am taking in consideration the fact that checks might be on different days)
I think the best approach is to use a correlated subquery to get the previous date and join back to the original table. This ensures that you get the previous record, even if there is more or less than a 1 month lag.
So the right query looks like:
select t.*, tprev.date, tprev.meter
from (select t.*,
(select top 1 date from t t2 where t2.date < t.date order by date desc
) prevDate
from t
) join
t tprev
on tprev.date = t.prevdate
In an environment such as the one you describe, it is very important not to make assumptions about the frequency of reading the meter. Although they may be read on average once per month, there will always be exceptions.
Testing with the following data:
HousholdID Date Meter
0 01/12/2012 100
1 01/12/2012 130
0 01/01/2013 120
1 01/01/2013 140
0 01/02/2013 120
1 01/02/2013 140
The following query:
SELECT a.housholdid,
a.date,
b.date,
a.meter,
b.meter,
a.meter - b.meter AS Consumption
FROM (SELECT *
FROM water
WHERE Month([date]) = Month(Date())
AND Year([date])=year(Date())) a
LEFT JOIN (SELECT *
FROM water
WHERE DateSerial(Year([date]),Month([date]),Day([date]))
=DateSerial(Year(Date()),Month(Date())-1,Day([date])) ) b
ON a.housholdid = b.housholdid
The above query selects the records for this month Month([date]) = Month(Date()) and compares them to records for last month ([date]) = Month(Date()) - 1)
Please do not use Date as a field name.
Returns the following result.
housholdid a.date b.date a.meter b.meter Consumption
0 01/02/2013 01/01/2013 120 100 20
1 01/02/2013 01/01/2013 140 130 10
Try
select t.householdID
, max(s.theDate) as billingMonth
, max(s.meter)-max(t.meter) as waterUsed
from myTbl t join (
select householdID, max(theDate) as theDate, max(meter) as meter
from myTbl
group by householdID ) s
on t.householdID = s.householdID and t.theDate <> s.theDate
group by t.householdID
This works in SQL not sure about access
You can use the LAG() function in certain SQL dialects. I found this to be much faster and easier to read than joins.
Source: http://blog.jooq.org/2015/05/12/use-this-neat-window-function-trick-to-calculate-time-differences-in-a-time-series/