I have one database and time to time i change some part of query as per requirement.
i want to keep record of results of both before and after result of these queries in one table and want to show queries which generate difference.
For Example,
Consider following table
emp_id country salary
---------------------
1 usa 1000
2 uk 2500
3 uk 1200
4 usa 3500
5 usa 4000
6 uk 1100
Now, my before query is :
Before Query:
select count(emp_id) as count,country from table where salary>2000 group by country;
Before Result:
count country
2 usa
1 uk
After Query:
select count(emp_id) as count,country from table where salary<2000 group by country;
After Query Result:
count country
2 uk
1 usa
My Final Result or Table I want is:
column 1 | column 2 | column 3 | column 4 |
2 usa 2 uk
1 uk 1 usa
...... but if query results are same than it shouldn't show in this table.
Thanks in advance.
I believe that you can use the same approach as here.
select t1.*, t2.* -- if you need specific columns without rn than you have to list them here
from
(
select t.*, row_number() over (order by count) rn
from
(
-- query #1
select count(emp_id) as count,country from table where salary>2000 group by country;
) t
) t1
full join
(
select t.*, row_number() over (order by count) rn
from
(
-- query #2
select count(emp_id) as count,country from table where salary<2000 group by country;
) t
) t2 on t1.rn = t2.rn
Related
This is what I have:
AirlineName Departure_City No_of_DepartureCity Arrival_City No_of_ArrivalCity
---------------------------------------------------------------------------------------------------- -------------- ------------------- ------------ -----------------
Air Asia MY 2 JPN 2
Emirates Airlines MY 2 JPN 2
Malaysia Airlines MY 2 GER 2
Malaysia Airlines MY 1 JPN 1
Air Asia MY 1 KOR 1
This is what I want:
AirlineName Departure_City No_of_DepartureCity Arrival_City No_of_ArrivalCity
---------------------------------------------------------------------------------------------------- -------------- ------------------- ------------ -----------------
Air Asia MY 2 JPN 2
Emirates Airlines MY 2 JPN 2
Malaysia Airlines MY 2 GER 2
I have already written a query to retrieve the most frequent data for Departure_City and Arrival_City, but I can't make it grouped together and only show the most frequent data for each AirlineName.
This is my query so far:
SELECT Airline.AirlineName, Flight_Schedule.Departure_City, COUNT(Flight_Schedule.Departure_City) AS No_of_DepartureCity, Flight_Schedule.Arrival_City, COUNT(Flight_Schedule.Arrival_City) AS No_of_ArrivalCity
FROM Airline
LEFT JOIN Aircraft ON Airline.AirlineID = Aircraft.AirlineID
LEFT JOIN Flight_Schedule ON Aircraft.AircraftID = Flight_Schedule.AircraftID
GROUP BY Airline.AirlineName, Flight_Schedule.Departure_City, Flight_Schedule.Arrival_City
ORDER BY COUNT(Flight_Schedule.Departure_City)DESC , COUNT(Flight_Schedule.Arrival_City) DESC
You can make use of Rank or Dense_rank (If you want to select more than two rows having same number of cities) function
Demo
with CTE1 AS(
SELECT A.*,
RANK() OVER(PARTITION BY AirlineName ORDER BY No_of_ArrivalCity desc) as rn
FROM TABLE1 A)
SELECT * FROM CTE1 where rn = 1;
As you're grouping by lots of columns, instead of just 'AirlineName' it's grouping by all of the different values across those number of columns.
To return the number of AirlineName's and their frequency try this:
SELECT Airline.AirlineName, COUNT(*) AS [COUNT]
FROM Airline
GROUP BY Airline.AirlineName
ORDER BY COUNT(*) DESC
If you need the additional columns then your code is already correct, because of how you are grouping it and the individual values contained within the columns.
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)
I am hoping someone can help me with my query.
I have a table with the columns, 'Date', 'ID_Num and 'Name'. What I want to do is add a column at the end to show the total amount of times each ID_Num is within the data but based on the date. So although 'ID_Num' 1001 shows 4 times in total, it is twice on the 20/04/2018 and once on both the 21/04/2018 and 22/04/2018.
EDIT: I should have stipulated that I will be pulling several other columns with information, which I cant use a group by on everything.
Date ID_Num Name Count
20/04/2018 1001 John 2
20/04/2018 1001 John 2
20/04/2018 1002 Paul 2
20/04/2018 1002 Paul 2
20/04/2018 1003 David 2
20/04/2018 1003 David 2
20/04/2018 1004 Stephen 1
21/04/2018 1001 John 1
21/04/2018 1002 Paul 3
21/04/2018 1002 Paul 3
21/04/2018 1002 Paul 3
21/04/2018 1004 Stephen 1
22/04/2018 1001 John 1
22/04/2018 1002 Paul 1
22/04/2018 1003 David 1
22/04/2018 1004 Stephen 1
Thanks
Unless I'm missing something here, a simple group by and count should do it:
SELECT Date, ID_Num, Name, Count(*)
FROM TableName
GROUP BY Date, ID_Num, Name
(That is, assuming there can only be one Name for each ID_Num)
Update
Assuming your rdbms supports it, you can use count with an over clause:
SELECT Date, ID_Num, Name, Count(*) OVER(PARTITION BY Date, Id_Num)
FROM TableName
If not, you can use a sub query:
SELECT Date,
ID_Num,
Name,
(SELECT Count(*)
FROM TableName As t1
WHERE t1.Date = t0.Date
AND t1.ID_NUM = t0.ID_NUM)
FROM TableName As t0
Try this:
SELECT
Date,
Id_num,
count(*) count
FROM
tabel_name
GROUP BY
Date,
Id_num
If you want name as well:
SELECT
Date,
Id_num,
Name
count(*) count
FROM
tabel_name
GROUP BY
Date,
Id_num,
Name
You can use a normal select query and then add a sub query to do a group and show the total. Simple example below
SELECT Date, ID_Num, Name,
(SELECT Count(ID_Num) FROM TableName AS CHILD WHERE CHILD.Id_Num = Parent.Id_Num) AS Total
FROM TableName AS Parent
I've tried more or less all combinations of count and distinct (except the correct one :) ) in order to get the example below.
Input: table t1
NAME | FOOD
Mary | Apple
Mary | Banana
Mary | Apple
Mary | Strawberry
John | Cherries
Expected output:
NAME | FOOD
Mary | 3
John | 1
N.B. Mary has Apple in two rows but she has 3 as we have 3 different values in the column.
I only managed to get 4 in FOOD Column for her, but I need 3 :(
select a.name as NAME, a.count(name) as Food
from
(SELECT distinct NAME,Food from table)a
Start with a query which gives you unique combinations of NAME and FOOD:
SELECT DISTINCT t1.NAME, t1.FOOD
FROM t1
Then you can use that as a subquery in another where you can GROUP BY and Count:
SELECT sub.NAME, Count(*) AS [FOOD]
FROM
(
SELECT DISTINCT t1.NAME, t1.FOOD
FROM t1
) AS sub
GROUP BY sub.NAME;
select a.name, sum(a.FoodCount) from(
select distinct name,COUNT(food) as FoodCount from #t1 group by name, food ) as a group by a.name order by 2 desc
I've got the following table:
ID Name Sales
1 Kalle 1
2 Kalle -1
3 Simon 10
4 Simon 20
5 Anna 11
6 Anna 0
7 Tina 0
I want to write a SQL query that only returns the rows that
represents a salesperson with sum of sales > 0.
ID Name Sales
3 Simon 10
4 Simon 20
5 Anna 11
6 Anna 0
Is this possible?
You can easily get names of the people with the sum of sales that are greater than 0 by using the a HAVING clause:
select name
from yourtable
group by name
having sum(sales) > 0;
This query will return both Simon and Anna, then if you want to return all of the details for each of these names you can use the above in a WHERE clause to get the final result:
select id, name, sales
from yourtable
where name in (select name
from yourtable
group by name
having sum(sales) > 0);
See SQL Fiddle with Demo.
You can make it like this, I think the join will be more effective than the where name in() clause.
SELECT Sales.name, Sales.sales
FROM Sales
JOIN (SELECT name FROM Sales GROUP BY Sales.name HAVING SUM(sales) > 0) AS Sales2 ON Sales2.name = Sales.name
This will work on some databases, like oracle, mssql, db2
SELECT ID, Name, Sales
FROM
(
SELECT ID, Name, Sales, sum(sales) over (partition by name) sum1
FROM <table>
) a
WHERE sum1 > 0