I have a table as below on sql.
OrderID Account OrderMethod OrderDate DispatchDate DispatchMethod
2145 qaz 14 20/3/2011 23/3/2011 2
4156 aby 12 15/6/2011 25/6/2011 1
I want to count all records that have reordered 'within 30 days' of dispatch date where Dispatch Method is '2' and OrderMethod is '12' and it has come from the same Account.
I want to ask if this all can be achieved with one query or do I need to create different tables and do it in stages as I think I wll have to do now? Please can someone help with a code/query?
Many thanks
T
Try the following, replacing [tablename] with the name of your table.
SELECT Count(OriginalOrders.OrderID) AS [Total_Orders]
FROM [tablename] AS OriginalOrders
INNER JOIN [tablename] AS Reorders
ON OriginalOrders.Account = Reorders.Account
AND OriginalOrders.OrderDate < Reorders.OrderDate
AND DATEDIFF(day, OriginalOrders.DispatchDate, Reorders.OrderDate) <= 30
AND Reorders.DispatchMethod = '2'
AND Reorders.OrderMethod = '12';
By using an inner join you'll be sure to only grab orders that meet all the criteria.
By linking the two tables (which are essentially the same table with itself using aliases) you make sure only orders under the same account are counted.
The results from the join are further filtered based on the criteria you mentioned requiring only orders that have been placed within 30 days of the dispatch date of a previous order.
Totally possible with one query, though my SQL is a little stale..
select count(*) from table
where DispatchMethod = 2
AND OrderMethod = 12
AND DATEDIFF(day, OrderDate, DispatchDate) <= 30;
(Untested, but it's something similar)
One query can do it.
SELECT COUNT(*)FROM myTable reOrder
INNER JOIN myTable originalOrder
ON reOrder.Account = originalOrder.Account
AND reOrder.OrderID <> originalOrder.OrderID
-- all re-orders that are within 30 days or the
-- original orders dispatch date
AND DATEDIFF(d, originalOrder.DispatchDate, reOrder.OrderDate) <= 30
WHERE reOrder.DispatchMethod = 2
AND reOrder.OrderMethod = 12
You need a self-join.
The query below assumes that a given account will have either 1 or 2 records in the table - 2 if they've reordered, else 1.
If 3 records exist for a given account, 2 orders + 1 reorder then this won't work - but we'd then need more information on how to distinguish between an order and a reorder.
SELECT COUNT(*) FROM myTable new, myTable prev
WHERE new.DispatchMethod = 2
AND new.OrderMethod = 12
AND DATEDIFF(day, prev.DispatchDate, new.OrderDate) <=30
AND prev.Account == new.Account
AND prev.OrderDate < new.OrderDate
Can we use GROUP BY in this case, such as the following?
SELECT COUNT(Account)
FROM myTable
WHERE DispatchMethod = 2 AND OrderMethod = 12
AND DATEDIFF(d, DispatchDate, OrderDate) <=30
GROUP BY Account
Will the above work or am I missing something here?
Related
Right now I have a query that lets me know which users didn't make a purchase 12 months prior to becoming members. These users have MEM_PRE_12=0 and I want to filter off those users more natively using SQL partitions rather than always putting rudimentary WHERE criteria.
Here is the SQL I use to find the users I want/don't want.
SELECT SUM(CASE WHEN DATE <= DATEADD(month, -12, U.INSERTED_AT) THEN 1 ELSE 0 END) AS MEM_PRE_12, I.CLIENTID, I.INSTALLATIONID
FROM <<<My_Joined_Tables>>>
GROUP BY I.CLIENTID, I.INSTALLATIONID
HAVING MEM_PRE_12 != 0
ORDER BY MEM_PRE_12
After this I'm going to have to go back and say where I.CLIENTID in the above nested query and select the actual information I want from users who made purchases greater than their insertion date.
How can I do this without so much nesting of all these joined tables?
If you want the detailed rows for customers who made a purchase in the last 12 months, you can use window functions:
with q as (
<whatever your query logic is>
)
select q.*
from (select q.*,
SUM(CASE WHEN DATE <= DATEADD(month, -12, U.INSERTED_AT) THEN 1 ELSE 0 END) over (partition by CLIENTID, INSTALLATIONID) as AS MEM_PRE_12
from q
) q
where mem_pre_12 > 0;
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
;
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/
I am writing a stored procedure in SQL Server Management Studio 2005 to return a list of states and policy counts for two different time periods, month to date and year to date. I have created a couple of views to gather the required data and a stored procedure for use in a Reporting Services report.
Below is my stored procedure:
SELECT DISTINCT
S.[State],
COUNT(HP_MTD.PolicyID) AS PolicyCount_MTD,
COUNT(HP_YTD.PolicyID) AS PolicyCount_YTD
FROM tblStates S
LEFT OUTER JOIN vwHospitalPolicies HP_MTD ON S.[State] = HP.[State]
AND HP.CreatedDate BETWEEN DATEADD(MONTH, -1, GETDATE()) AND GETDATE()
LEFT OUTER JOIN vwHospitalPolicies HP_YTD ON S.[State] = HP.[State]
AND HP.CreatedDate BETWEEN DATEADD(YEAR, -1, GETDATE()) AND GETDATE()
GROUP BY S.[State]
ORDER BY S.[State] ASC
The problem I am running into is my counts are bloating when a second LEFT OUTER JOIN is added, even the COUNT() that isn't referencing the second join. I need a left join since not all states will have policies for the given period, but they should still appear on the report.
Any suggestions would be greatly appreciated!
It sounds like you need:
COUNT(DISTINCT HP_MTD.PolicyID) AS PolicyCount_MTD,
COUNT(DISTINCT HP_YTD.PolicyID) AS PolicyCount_YTD
instead of:
COUNT(HP_MTD.PolicyID) AS PolicyCount_MTD,
COUNT(HP_YTD.PolicyID) AS PolicyCount_YTD
Your original query is including the number of matching rows in the second join. Adding a DISTINCT clause inside the COUNT limits it to unique occurrences of the PolicyID.
I prefer CTEs for this sort of work - they're basically a sort of inline view.
Your actual problem is that some policies are being counted twice - once for the month-to-date, and once for the year-to-date - in both count columns. So, if you have source tables like this:
year-to-date
state policy
==================
1 1
1 2
1 3
2 4
month-to-date
state policy
==================
1 1
1 2
The result table for the JOINs (before COUNT is assesed) looks like this:
temp
state monthPolicy yearPolicy
================================
1 1 1
1 1 2
1 1 3
1 2 1
1 2 2
1 2 3
2 - 4
Clearly not what you want. Often, the solution is to use a CTE or other table reference to present summed-up records for the final join. Something like this:
WITH PoliciesMonthToDate (state, count) as (
SELECT state, COUNT(*)
FROM vwHospitalPolicies
WHERE createdDate >= DATEADD(MONTH, -1, GETDATE())
AND createdDate < DATEADD(DAY, 1, GETDATE())
GROUP BY state),
PoliciesYearToDate (state, count) as (
SELECT state, COUNT(*)
FROM vwHospitalPolicies
WHERE createdDate >= DATEADD(YEAR, -1, GETDATE())
AND createdDate < DATEADD(DAY, 1, GETDATE())
GROUP BY state)
SELECT a.state, COALESCE(b.count, 0) as policy_count_mtd,
COALESCE(c.count, 0) as policy_count_ytd
FROM tblStates a
LEFT JOIN PoliciesMonthToDate b
ON b.state = a.state
LEFT JOIN PoliciesYearToDate c
ON c.state = a.state
ORDER BY a.state
(minor nitpick - don't use prefixes for tables and views. It's noise, and if for some reason you switch between them, it would require a code change. That, or the name would then be misleading)
My database isn't actually customers and orders, it's customers and prescriptions for their eye tests (just in case anyone was wondering why I'd want my customers to make orders less frequently!)
I have a database for a chain of opticians, the prescriptions table has the branch ID number, the patient ID number, and the date they had their eyes tested. Over time, patients will have more than one eye test listed in the database. How can I get a list of patients who have had a prescription entered on the system more than once in six months. In other words, where the date of one prescription is, for example, within three months of the date of the previous prescription for the same patient.
Sample data:
Branch Patient DateOfTest
1 1 2007-08-12
1 1 2008-08-30
1 1 2008-08-31
1 2 2006-04-15
1 2 2007-04-12
I don't need to know the actual dates in the result set, and it doesn't have to be exactly three months, just a list of patients who have a prescription too close to the previous prescription. In the sample data given, I want the query to return:
Branch Patient
1 1
This sort of query isn't going to be run very regularly, so I'm not overly bothered about efficiency. On our live database I have a quarter of a million records in the prescriptions table.
Something like this
select p1.branch, p1.patient
from prescription p1, prescription p2
where p1.patient=p2.patient
and p1.dateoftest > p2.dateoftest
and datediff('day', p2.dateoftest, p1.dateoftest) < 90;
should do... you might want to add
and p1.dateoftest > getdate()
to limit to future test prescriptions.
This one will efficiently use an index on (Branch, Patient, DateOfTest) which you of course should have:
SELECT Patient, DateOfTest, pDate
FROM (
SELECT (
SELECT TOP 1 DateOfTest AS last
FROM Patients pp
WHERE pp.Branch = p.Branch
AND pp.Patient = p.Patient
AND pp.DateOfTest BETWEEN DATEADD(month, -3, p.DateOfTest) AND p.DateOfTest
ORDER BY
DateOfTest DESC
) pDate
FROM Patients p
) po
WHERE pDate IS NOT NULL
On way:
select d.branch, d.patient
from data d
where exists
( select null from data d1
where d1.branch = d.branch
and d1.patient = d.patient
and "difference (d1.dateoftest ,d.dateoftest) < 6 months"
);
This part needs changing - I'm not familiar with SQL Server's date operations:
"difference (d1.dateoftest ,d.dateoftest) < 6 months"
Self-join:
select a.branch, a.patient
from prescriptions a
join prescriptions b
on a.branch = b.branch
and a.patient = b.patient
and a.dateoftest > b.dateoftest
and a.dateoftest - b.dateoftest < 180
group by a.branch, a.patient
This assumes you want patients who visit the same branch twice. If you don't, take out the branch part.
SELECT Branch
,Patient
FROM (SELECT Branch
,Patient
,DateOfTest
,DateOfOtherTest
FROM Prescriptions P1
JOIN Prescriptions P2
ON P2.Branch = P1.Branch
AND P2.Patient = P2.Patient
AND P2.DateOfTest <> P1.DateOfTest
) AS SubQuery
WHERE DATEDIFF(day, SubQuery.DateOfTest, SubQuery.DateOfOtherTest) < 90