In a firebird database with a table "Sales", I need to select the first sale of all customers. See below a sample that show the table and desired result of query.
---------------------------------------
SALES
---------------------------------------
ID CUSTOMERID DTHRSALE
1 25 01/04/16 09:32
2 30 02/04/16 11:22
3 25 05/04/16 08:10
4 31 07/03/16 10:22
5 22 01/02/16 12:30
6 22 10/01/16 08:45
Result: only first sale, based on sale date.
ID CUSTOMERID DTHRSALE
1 25 01/04/16 09:32
2 30 02/04/16 11:22
4 31 07/03/16 10:22
6 22 10/01/16 08:45
I've already tested following code "Select first row in each GROUP BY group?", but it did not work.
In Firebird 2.5 you can do this with the following query; this is a minor modification of the second part of the accepted answer of the question you linked to tailored to your schema and requirements:
select x.id,
x.customerid,
x.dthrsale
from sales x
join (select customerid,
min(dthrsale) as first_sale
from sales
group by customerid) p on p.customerid = x.customerid
and p.first_sale = x.dthrsale
order by x.id
The order by is not necessary, I just added it to make it give the order as shown in your question.
With Firebird 3 you can use the window function ROW_NUMBER which is also described in the linked answer. The linked answer incorrectly said the first solution would work on Firebird 2.1 and higher. I have now edited it.
Search for the sales with no earlier sales:
SELECT S1.*
FROM SALES S1
LEFT JOIN SALES S2 ON S2.CUSTOMERID = S1.CUSTOMERID AND S2.DTHRSALE < S1.DTHRSALE
WHERE S2.ID IS NULL
Define an index over (customerid, dthrsale) to make it fast.
in Firebird 3 , get first row foreach customer by min sales_date :
SELECT id, customer_id, total, sales_date
FROM (
SELECT id, customer_id, total, sales_date
, row_number() OVER(PARTITION BY customer_id ORDER BY sales_date ASC ) AS rn
FROM SALES
) sub
WHERE rn = 1;
İf you want to get other related columns, This is where your self-answer fails.
select customer_id , min(sales_date)
, id, total --what about other colums
from SALES
group by customer_id
So simple as:
select CUSTOMERID min(DTHRSALE) from SALES group by CUSTOMERID
Related
I'm working on a customers database and I want to get all data for their second purchase (for all of our customer weather they have 2 or more purchases).
For example:
Customer_ID Order_ID Order_Date
1 259 09/05/2020
1 644 03/11/2020
1 617 18/04/2022
4 834 22/09/2021
4 995 07/02/2022
I want to display the second order which is:
Customer_ID Order_ID Order_Date
1 644 03/11/2020
4 995 07/02/2022
I'm facing some difficulties in finding the right logic, any idea how I can achieve my end goal? :)
*Note: I'm using snowflake
You can use a ROW_NUMBER and filter using QUALIFY clause:
select * from table qualify row_number() over(partition by customer_id order by order_date) = 2;
You can use common table expression
with CTE_RS
AS (
SELECT Customer_ID,ORDER_ID,Order_Date,ROW_NUMBER() OVER(PARTITION BY Customer_ID ORDER BY Order_Date ) ORDRNUM FROM *TABLE NAME*
)
SELECT Customer_ID,ORDER_ID,Order_Date
FROM CTE_RS
WHERE ORDRNUM = 2 ;
I'm trying to do a simple Select query by getting the country based on the MAX Last update from the other table.
Order#
1
2
3
4
The other table contains the country and the last update:
Order# Cntry Last Update
1 12/21/2019 9:19 PM
1 US 1/10/2020 1:07 AM
2 JP 7/29/2020 12:15 PM
3 CA 4/12/1992 2:04 PM
3 GB 11/6/2001 9:26 AM
3 DK 2/1/2005 3:04 AM
4 CN 8/20/2013 12:04 AM
4 10/1/2015 4:04 PM
My desired result:
Order# Country
1 US
2 JP
3 DK
4
Not sure the right solution for this. So far i'm stuck with this:
SELECT Main.[Order#], tempTable.Cntry
FROM Main
LEFT JOIN (
SELECT [Order#], Cntry, Max([Last Update]) as LatestDate FROM Country
GROUP BY [Order#], Cntry
) as tempTable ON Main.[Order#] = tempTable.[Order#];
Thanks in advance!
If needs only number of order and country,maybe don't need two tables:
SELECT distinct order, country
FROM
(
SELECT order, LAST_VALUE (country) OVER (PARTITION by [order] order by last_update) country FROM Country
) X
In SQL Server, you can use a correlated subquery:
update main
set country = (select top (1) s.country
from secondtable s
where s.order# = main.order#
order by s.lastupdate desc
);
EDIT:
A select would look quite simimilar:
select m.*,
(select top (1) country
from secondtable s
where s.order# = main.order#
order by s.lastupdate desc
)
from main m
I don't have time to try it with sample data, but is that what you are looking for?
select order orde, cntry
from table
where last_update =
(select max(last_update) from table where order = orde)
every customer has different first-time purchase date, I want to COUNT the number of purchases they have between the following 10 months after the first purchase?
sample table
TransactionID Client_name PurchaseDate Revenue
11 John Lee 10/13/2014 327
12 John Lee 9/15/2015 873
13 John Lee 11/29/2015 1,938
14 Rebort Jo 8/18/2013 722
15 Rebort Jo 5/21/2014 525
16 Rebort Jo 2/4/2015 455
17 Rebort Jo 3/20/2016 599
18 Tina Pe 10/8/2014 213
19 Tina Pe 6/10/2016 3,494
20 Tina Pe 8/9/2016 411
my code below just use ROW_NUM function to identify the first purchase, but I don't know how to do the calculations or there's a better way to do it?
SELECT client_name,
purchasedate,
Dateadd(month, 10, purchasedate) TenMonth,
Row_number()
OVER (
partition BY client_name
ORDER BY client_name) RM
FROM mytable
You might try something like this - I assume you're using SQL Server from the presence of DATEADD() and the fact that you're using a window function (ROW_NUMBER()):
WITH myCTE AS (
SELECT TransactionID, Client_name, PurchaseDate, Revenue
, MIN(PurchaseDate) OVER ( PARTITION BY Client_name ) AS min_PurchaseDate
FROM myTable
)
SELECT Client_name, COUNT(*)
FROM myCTE
WHERE PurchaseDate <= DATEADD(month, 10, min_PurchaseDate)
GROUP BY Client_name
Here I'm creating a common table expression (CTE) with all the data, including the date of first purchase, then I grab a count of all the purchases within a 10-month timeframe.
Hope this helps.
Give this a whirl ... Subquery to get the min purchase date, then LEFT JOIN to the main table to have a WHERE clause for the ten month date range, then count.
SELECT Client_name, COUNT(mt.PurchaseDate) as PurchaseCountFirstTenMonths
FROM myTable mt
LEFT JOIN (
SELECT Client_name, MIN(PurchaseDate) as MinPurchaseDate GROUP BY Client_name) mtmin
ON mt.Client_name = mtmin.Client_name AND mt.PurchaseDate = mtmin.MinPurchaseDate
WHERE mt.PurchaseDate >= mtmin.MinPurchaseDate AND mt.PurchaseDate <= DATEADD(month, 10, mtmin.MinPurchaseDate)
GROUP BY Client_name
ORDER BY Client_name
btw I'm guessing there's some kind of ClientID involved, as nine character full name runs the risk of duplicates.
I am trying to develop a query to pull out the top 2 months of sales by customer id. Here is a sample table:
Customer_ID Sales Amount Period
144567 40 2
234567 50 5
234567 40 7
144567 80 10
144567 48 2
234567 23 7
desired output would be
Customer_ID Sales Sum Period
144567 80 10
144567 48 2
234567 50 5
234567 40 7
I've tried
select sum(net_sales_usd_spot), valid_period, customer_id
from sales_trans_price_output
where valid_period in (select valid_period, sum(net_sales_usd_spot)
from sales_trans_price_output
where rank<=2)
group by valid_period, customer_id
error is
too many values ORA-00913.
I see why, but not sure how to rework it.
Try:
SELECT *
FROM (
SELECT t.*,
row_number() over (partition by customer_id order by sales_amount desc ) rn
FROM sales_trans_price t
)
WHERE rn <= 2
ORDER BY 1,2 desc
Demo: http://sqlfiddle.com/#!4/882888/3
what if you change your where clause to:
where valid_period in
(
select p.valid_period from sales_trans_price_output p
join (select valid_period, sum(net_sales_usd_spot)
from sales_trans_price_output
where rank<=2) s on s.valid_period = p.valid_period
)
It might be ugly and need refactoring, but I think this is the logic you're after.
The error is because of this.
where valid_period in (select valid_period, sum(net_sales_usd_spot)
from sales_trans_price_output
where rank<=2)
The subquery can only contain one field.
You are on the right track using rank, but you might not be using it correctly. Google oracle rank to find the correct syntax.
Back to what you are looking to achieve, a derived table is the approach I would use. That's simply a subquery with an alias. Or, if you use the keyword with, it might be called a CTE - Computed Table Expression.
Try it
SELECT * FROM (
SELECT T.*,
RANK () OVER (PARTITION BY CUSTOMER_ID
ORDER BY VALID_PERIOD DESC) FN_RANK
FROM SALES_TRANS_PRICE_OUTPUT T
) A
WHERE A.FN_RANK <= 2
ORDER BY CUSTOMER_ID ASC, VALID_PERIOD DESC, FN_RANK DESC
I am using SQL Server 2008 and I was wondering how to remove duplicate customers either from the table or exclude it in my query. An Account_ID can only have 1 product associated with it. And the account with the most recent purchase date is what should be showing. An example is below:
Account_ID, Account_Purchase, Purchase_Date
1 Product 1 1/1/2016
2 Product 1 1/2/2016
3 Product 2 1/5/2016
1 Product 3 3/12/2016
4 Product 3 1/5/2016
Ideally I would only see:
Account_ID, Account_Purchase, Purchase_Date
2 Product 1 1/2/2016
3 Product 2 1/5/2016
1 Product 3 3/12/2016
4 Product 3 1/5/2016
This should not show up because it is not the most recent purchase from account 1
Account_ID, Account_Purchase, Purchase_Date
1 Product 1 1/1/2016
Thank you all for help, folks!
Simply acquire the latest purchase_date using max and group by account_id. Then use inner join to get the other details from the acquired details.
SELECT TABLE_NAME.* FROM TABLE_NAME
INNER JOIN(
SELECT Account_ID, MAX(Purchase_Date) AS Purchase_Date
GROUP BY Account_ID
) LatestPurchases
ON TABLE_NAME.Account_ID = LatestPurchases.Account_ID
AND TABLE_NAME.Purchase_Date = LatestPurchases.Purchase_Date
Try below query, please replace TABLENAME with your table
WITH CTE
AS (
SELECT
*,
ROW_NUMBER() OVER (PARTITION BY Account_ID ORDER BY Purchase_Date DESC) AS RN
FROM TABLENAME
)
SELECT
*
FROM CTE
WHERE RN = 1
Here is another query
SELECT
t.Account_id,
t.Account_Purchase,
t.Purchase_Date
FROM
tablename t
WHERE
t.Purchase_Date = (SELECT MAX(Purchase_date) FROM Tablename WHERE Account_ID = t.Account_ID)
ORDER BY
t.Purchase_Date DESC