Objective 1:
Your sales data is stored in the Purchases table.
Your sales staff wants to see the sales data in a pivoted form, broken down by quarter.
If your Purchases table doesn't have sales data, create some. Be sure the data spans four quarters.
Next, write a query to pivot the data as follows:
Album Q1 Q2 Q3 Q4
OK Computer 2 5 3 7
Sea Change 8 6 2 1
Do not create a separate table or a view. Do not alter any tables.
Save your query as dba1lesson10project1.sql and hand in the project.
This is What I need to do. But, the table it wants me to work with looks like this. And it states in the assignment I cannot alter it at all.
CustomerID DateOfPurchase SongID
1 2007-03-31 3
3 2007-06-30 4
4 2007-09-30 4
5 2007-12-31 5
I have tried
SELECT SongID,
SUM(CASE WHEN DateOfPurchase = '2007-03-31' THEN DateOfPurchase ElSE 0 END) AS 'Q1',
SUM(CASE WHEN DateOfPurchase = '2007-06-30' THEN DateOfPurchase ELSE 0 END) AS 'Q2',
SUM(CASE WHEN DateOfPurchase = '2007-09-30' THEN DateOfPurchase ELSE 0 END) AS 'Q3',
SUM(CASE WHEN DateOfPurchase = '2007-12-31' THEN DateOfPurchase ELSE 0 END) AS 'Q4'
FROM Purchases
GROUP BY SongID;
Along with other variants:
SELECT SongID,
SUM(CASE WHEN DateOfPurchase = '2007-03-31' THEN CustomerID ElSE 0 END) AS 'Q1',
SUM(CASE WHEN DateOfPurchase = '2007-06-30' THEN CustomerID ELSE 0 END) AS 'Q2',
SUM(CASE WHEN DateOfPurchase = '2007-09-30' THEN CustomerID ELSE 0 END) AS 'Q3',
SUM(CASE WHEN DateOfPurchase = '2007-12-31' THEN CustomerID ELSE 0 END) AS 'Q4'
FROM Purchases
GROUP BY SongID;
And:
SELECT SongID,
SUM(CASE WHEN DateOfPurchase = '2007-03-31' THEN SongID ElSE 0 END) AS 'Q1',
SUM(CASE WHEN DateOfPurchase = '2007-06-30' THEN SongID ELSE 0 END) AS 'Q2',
SUM(CASE WHEN DateOfPurchase = '2007-09-30' THEN SongID ELSE 0 END) AS 'Q3',
SUM(CASE WHEN DateOfPurchase = '2007-12-31' THEN SongID ELSE 0 END) AS 'Q4'
FROM Purchases
GROUP BY SongID;
Which, the last 2 almost get me what I need. But, there is only one purchase per SongID and Quarter. They show me either the CustomerID or SongID instead. I have a basic understand of what I need to do. But without being able to alter the table to show how many purchases there have actually been I'm not sure what to do. Any suggestions?
Your current query is very close, I would suggest a few minor changes. You are hard-coding the date but what happens if you have a date in quarter one that is not equal to 2007-03-31 it won't show up.
I would use the QUARTER() function in MySQL, this will return the quarter 1-4 based on the date value.
Second, I don't think you want to sum the SongID, in your CASE expression I would replace the SongID with 1 similar to the following:
SELECT SongID,
SUM(CASE WHEN Quarter(DateOfPurchase) = 1 THEN 1 ElSE 0 END) AS Q1,
SUM(CASE WHEN Quarter(DateOfPurchase) = 2 THEN 1 ELSE 0 END) AS Q2,
SUM(CASE WHEN Quarter(DateOfPurchase) = 3 THEN 1 ELSE 0 END) AS Q3,
SUM(CASE WHEN Quarter(DateOfPurchase) = 4 THEN 1 ELSE 0 END) AS Q4
FROM Purchases
GROUP BY SongID;
See SQL Fiddle with Demo
You can do this quarterly report easily using MySQL Pivot table generator.
While creating your report, you will be asked to add the "Column settings "
Please choose the "Purchasing table" as the "Table", the column that contains the date values as the "Field" . Once selecting a date value, a function menu should appear, please select "Quarter" to get your pivot table divided in quarters as you requested. please note that you have the option to create a report for one specific year if you like and in this case you should check the "Exact Year" Box and add a specific year otherwise leave the "Exact year" box unchecked .
The final report will be able to see something like this report :
http://mysqlpivottable.net/MySQL-Pivot-Table-Demo/tables/Quarterly_Sales_Report/
Related
I have 70 different types of accounts. And I am fetching the data as per the account type.
The query like this,
$mainData = "SELECT
count(*) AS totalRows,
sum(pay) as totalPay
sum(case when account_type = 1 then 1 else 0 end) AS account_1_Total,
sum(case when account_type = 1 then pay else 0 end) AS account_1_Pay,
sum(case when account_type = 2 then 1 else 0 end) AS account_2_Total,
sum(case when account_type = 2 then pay else 0 end) AS account_2_Pay,
{all_account_types_here}
FROM account_table";
In the end, those sum() are about more than 140.
So the question is, how many sum() is recommended in a single query?
Thanks!
EDITED:
The GROUP BY is the solution of it.
I have made an attendance system for a project, However I'm stuck right now by trying to create a query.
SELECT
COUNT(Students.idStudents) total,
SUM(case when Attendance.status LIKE 'present' then 1 else 0 end) present,
SUM(case when Attendance.status LIKE 'late' then 1 else 0 end) late,
SUM(case when Attendance.status is null then 1 else 0 end) absents
FROM Students, Schools, Tags LEFT JOIN Attendance
ON Attendance.tagCode = Tags.tagCode
WHERE Schools.idSchools = Students.idSchools
AND Tags.idStudents = Students.idStudents
This code works and generates an attendance. However this will show all the dates.
When I add in another line to specify date
AND Attendance.date = DATE(NOW());
It will not show anything..
There's 'Present', 'Late' status for the attendance however if the student's record in that table doesn't exist, it is considered as absent.
How do I do that?
Assuming you're using a case insensitive collation, your purported solution can be rewritten as follows:
SELECT COUNT(p.idStudents) total
, SUM(CASE WHEN a.status = 'present' THEN 1 ELSE 0 END) present -- [or just SUM(a.status = 'present')]
, SUM(CASE WHEN a.status = 'late' THEN 1 ELSE 0 END) late
, SUM(CASE WHEN a.status IS NULL THEN 1 ELSE 0 END) absents
FROM Students p
JOIN Schools s
ON s.idSchools = p.idSchools
JOIN Tags t
ON t.idStudents = p.idStudents
LEFT
JOIN Attendance a
ON a.tagCode = t.tagCode
AND a.date = CURDATE() ;
For next time: Your ERD shows 10 tables, but only 4 feature in this problem. If a table isn't likely to be part of the proposed solution, don't show it. Don't provide pictures. Instead, where possible, provide proper DDLs (and/or an sqlfiddle), TOGETHER WITH THE DESIRED RESULT SET based upon a minimal, but properly representative data set.
Welcome to SO.
Figured it out..
SELECT
COUNT(Students.idStudents) total,
SUM(case when Attendance.status LIKE 'present' then 1 else 0 end) present,
SUM(case when Attendance.status LIKE 'late' then 1 else 0 end) late,
SUM(case when Attendance.status is null then 1 else 0 end) absents
FROM Students, Schools, Tags LEFT JOIN (SELECT * FROM Attendance WHERE Attendance.date = NOW()) AS Attendance
ON Attendance.tagCode = Tags.tagCode
WHERE Schools.idSchools = Students.idSchools
AND Tags.idStudents = Students.idStudents
The problem with the original query was you were asking for students where their attendance was "NOW" where no student was ever now but they are current attending classes. They may have signed in at 8am and you run the query at 10am. You'd need to manipulate the datetime to choose your start time and end time based on the current day.
timestampadd(HOUR, 08, CURDATE()) - this will give you 8am, you'd then query for when attendance.date is greater than or equal to 8am and then potentially less than or equal to 4pm?
I have a table which looks something like the following...
id price condition sell
21039 20.40 new 0
21039 20.41 used 1
12378 10.40 new 1
12378 5 used 0
45898 30.30 new 1
45898 12.20 used 0
(note: there will only ever be 1 new and used value for each id)
What I am trying to do is group all rows with the same id number but in the process creating new columns for each condition, which should look something like...
id new_price new_sell used_price new_sell
21039 20.40 0 20.41 1
12378 10.40 1 5 0
45898 30.30 1 12.20 0
All that I have come up with is the following query, which looks silly
SELECT id, price, condition,
IF(price > 3, 1, 0) AS sell
FROM products
GROUP BY id
How can I get the desired affect of the 2nd table.
This is known as a pivot table. It is done with a series of CASE statements for each column you need to produce, along with an aggregate MAX() or SUM() to eliminate NULLs and collapse it down to a single row.
SELECT
id,
SUM(CASE WHEN `condition` = 'new' THEN price ELSE 0 END) AS new_price,
SUM(CASE WHEN `condition` = 'new' THEN sell ELSE 0 END) AS new_sell,
SUM(CASE WHEN `condition` = 'used' THEN price ELSE 0 END) AS used_price,
SUM(CASE WHEN `condition` = 'used' THEN sell ELSE 0 END) AS used_sell
FROM
products
GROUP BY id
Without the SUM() and GROUP BY, you would still get 2 rows per id, with each having half its columns (not matched by condition in the CASE) as NULL. The SUM() (could also use MAX() in this case) eliminates the NULLs and produces one row since aggregate functions exclude NULL values while the GROUP BY groups the rows by id.
Here is a working sample on SQLFiddle.com
Update after comment:
To calculate sell based on the price, just replace the condition in the sell CASE statements:
SELECT
id,
SUM(CASE WHEN `condition` = 'new' THEN price ELSE 0 END) AS new_price,
SUM(CASE WHEN `condition` = 'new' AND price > 3 THEN 1 ELSE 0 END) AS new_sell,
SUM(CASE WHEN `condition` = 'used' THEN price ELSE 0 END) AS used_price,
SUM(CASE WHEN `condition` = 'used' AND price > 3 THEN 1 ELSE 0 END) AS used_sell
FROM
products
GROUP BY id
(Updated sample...)
I have a sql query for my MYSQL DB and want to limit the results to only 10 sales people instead of 20. I have tried inserting their names inside the query but keep getting error. Also is it possible to rank according to total. The sql query I am using is:
select sales_id, totalbuy, totalsell, totalbuy + totalsell as total from
(select sales_id, SUM(CASE WHEN side= 'buy' THEN 1 ELSE 0 END) AS totalbuy,
SUM(CASE WHEN side= 'sell' THEN 1 ELSE 0 END) AS totalsell
from sales_id where sales_id='sales1', GROUP BY sales_id)q
where it says sales1 I have attempted to add the remaining 9 sales_ids' using a comma and single quotes but can't get it to work.
If you want certain sales_id only, use the "IN " clause.
if you wanna only the top 10 total, remove that line and use LIMIT
select sales_id, totalbuy, totalsell, totalbuy + totalsell as total from
(select owner_id, SUM(CASE WHEN side= 'buy' THEN 1 ELSE 0 END) AS totalbuy,
SUM(CASE WHEN side= 'sell' THEN 1 ELSE 0 END) AS totalsell
from sales_id
where sales_id in ('sales1', 'sales2', 'sales3', 'sales4')-- if you wanna certain sales_id only
GROUP BY sales_id)q
order by total desc
limit 0, 10;--top 10 by total (bigger first)
I have a table named 'sales' with following fields
salesid (type: int)
stime (type: datetime)
status (type: enum, values: remaining OR cancelled OR done)
... and other fields
I need a query that can output as
SalesDate TotalSales TotalDone TotalRemaining TotalCancelled
2010-11-06 10 5 3 2
2010-11-06 15 14 1 0
Anyone know how to achieve this?
Help appreciated, thanks.
You can use conditional summation to get the results you want.
select stime as sales_date
,sum(1) as total_sales
,sum(case when status = 'remaining' then 1 else 0 end) as total_done
,sum(case when status = 'cancelled' then 1 else 0 end) as total_remaining
,sum(case when status = 'done' then 1 else 0 end) as total_cancelled
from sales
group by stime;
You can also use COUNT(expr) and exploit the fact it doesn't include NULLS, but personally I find that the above best conveys the intent of the developer.
Use a CASE statement in your SELECT to create pseudo columns using the status values of remaining, cancelled and done
SELECT
date(stime),
COUNT(salesid),
SUM(CASE status WHEN 'done' THEN 1 ELSE 0 END) as TotalDone,
SUM(CASE status WHEN 'remaining' THEN 1 ELSE 0 END) as TotalRemaining,
SUM(CASE status WHEN 'cancelled' THEN 1 ELSE 0 END) as TotalCancelled
FROM sales
GROUP BY date(stime)
Note: This is what i was trying to refer to. I think this should work but i have no access to MySQL to try out the syntax and verify it. Sorry about that. But this should get you going.