I am trying to merge all of these select statements and have the output display 5 different columns with the specified column names. I tried UNION but that is merging the values into one column. Also, I am using the round function to limit the number of decimal places for the average. Is there a better way to do this besides the round function? I am new to SQL.
(select round(avg("TotalPay")::int,2) as "($)Fire Department Average Pay"
from sf_fire sf)
(select round(avg("TotalPay")::int,2) as "($)Medicine Department Average Pay"
from sf_medicine sm)
select round(avg("TotalPay")::int,2) as "($)Police Department Average Pay"
from sfs_police sp
select round(avg("TotalPay")::int,2) as "($)Not dep Department Average Pay"
from sfs_notdep sn
select round(avg("TotalPay")::int,2) as "($)Other Department Average Pay"
from sfs_other so
Because this is a single row, you can do them as sub-selects.
select
(select round(avg("TotalPay")::int,2) from sf_fire) as '($)Fire Department Average Pay',
(select round(avg("TotalPay")::int,2) from sf_medicine) as '($)Medicine Department Average Pay',
(select round(avg("TotalPay")::int,2) from sfs_police) as '($)Police Department Average Pay',
(select round(avg("TotalPay")::int,2) from sfs_notdep) as '($)Not dep Department Average Pay',
(select round(avg("TotalPay")::int,2) from sfs_other) as '($)Other Department Average Pay';
Note that the column aliases go outside the sub-queries, and there's no need for table aliases.
Note: this suggests a single table might be better instead of multiple tables.
Related
I'm relatively new to PostgreSQL and I'm working with window functions.
I have 2 relations: company and employee. Employee contains an information about the salary. I just wanna to get a rating of employees by their salary in ascending order.
This is my query.
SELECT company.name,
e.last_name,
e.salary,
rank() OVER (ORDER BY e.salary nulls first )
FROM company
LEFT JOIN employee e ON e.company_id = company.id
order by company.name;
So
result is:
You can see that fourth and eighth rows have null-value salary. But first row with not null salary value is sixth - Kulakov got the third rank, but I need him to have the second rank.
I think it's possible not to count not null values.
What is the right way to do this?
table image
I have this table that I need to sort in the following way:
need to rank Departments by Salary;
need to show if Salary = NULL - 'No data to be shown' message
need to add total salary paid to the department
need to count people in the department
SELECT RANK() OVER (
ORDER BY Salary DESC
)
,CASE
WHEN Salary IS NULL
THEN 'NO DATA TO BE SHOWN'
ELSE Salary
,Count(Fname)
,Total(Salary) FROM dbo.Employees
I get an error saying:
Column 'dbo.Employees.Salary' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause.
Why so?
Column 'dbo.Employees.Salary' is invalid in the select list because it
is not contained in either an aggregate function or the GROUP BY
clause.
Why so?
The aggregate functions are returning a single value for the whole table, you can't SELECT a field alongside them it doesn't makes sense. Like say, you have a students table you apply Sum(marks) for the whole students table, and you are then also selecting student's name Select studentname in your query. Which student's name will the database engine select? Confusing
Column "invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause"
I tried this-
using inner query
SELECT RANK() OVER (ORDER BY SAL DESC) RANK,FNAME,DEPARTMENT
CASE
WHEN SAL IS NULL THEN 'NO DATA TO BE SHOWN'
ELSE SAL
END
FROM
(SELECT COUNT(FNAME) FNAME, SUM(SALARY) SAL, DEPARTMENT
FROM TESTEMPLOYEE
GROUP BY DEPARTMENT) t
I have two tables. One is Transactions and the other is Tickets. In Tickets I have the Ticket_Number,the name of the Category(Theater,Cinema,Concert), the Price of the Ticket. In Transactions I also have the Ticket_Number. What i want to do is to Get a SUM of money for each Category, and then with that data I want to Select the Category with the most money.
I already managed to get the SUM for each category but I am stuck here
SELECT category, SUM (Tickets.Price) AS Price
FROM Tickets,Transactions
WHERE Tickets.ticket_num=Transactions.ticket_num
GROUP BY Category
ORDER BY Price DESC;
I know i can add LIMIT 1 but I know it's not correct because 2 or more values can be the same
Using ROW_NUMBER to generate a sequence based on the sum of the price. Then, restrict to only the matching aggregated row with the highest total price.
WITH cte AS (
SELECT category, SUM(t1.Price) AS Price,
ROW_NUMBER() OVER (ORDER BY SUM(t1.Price) DESC) rn
FROM Tickets t1
INNER JOIN Transactions t2
ON t1.ticket_num = t2.ticket_num
GROUP BY Category
)
SELECT category, Price
FROM cte
WHERE rn = 1
ORDER BY Price DESC;
Note that if you want to capture all categories tied for the highest price, should a tie occur, then replace ROW_NUMBER in the above CTE with RANK, keeping everything else the same.
What you are looking for is a window function DENSE_RANK() which will handle ties properly.
RANK() will also work for your case, but if you would like to extend it to get TOP N places with ties (where N > 1), dense rank is the way to go.
SELECT Category, Price
FROM (
SELECT
Category,
SUM(ti.Price) AS Price,
DENSE_RANK() OVER (ORDER BY SUM(ti.Price) DESC) AS rnk
FROM Tickets ti
INNER JOIN Transactions tr ON
ti.ticket_num = tr.ticket_num
GROUP BY Category
) t
WHERE rnk = 1
I've also replaced the old style and not recommended joining of tables as comma separated list in FROM clause to a proper INNER JOIN clause and assigned aliases to tables.
You can use rank() to rank the sums of the prices, more expensive first.
SELECT category,
price
FROM (SELECT category,
sum(tickets.price) price,
rank() OVER (ORDER BY sum(tickets.price) DESC) r
FROM tickets
INNER JOIN transactions
ON transactions.ticket_num = tickets.ticket_num
GROUP BY category) x
WHERE r = 1;
I also took the liberty to rewrite your join from the ancient comma style to a modern, clearer version.
I have a query. this query is calculated percentage for every product. I created a virtual column on this query this columns name is 'yüzde'. After that, i want to transfer yüzde columns to another column in another table with update query if product ids are same.
I think I need to write a stored procedure. How can I do that?
SELECT [ProductVariantId] ,
count([ProductVariantId]) as bedensayısı,
count([ProductVariantId]) * 100.0 / (SELECT Top 1 Count(*) as Total
FROM [Live_ADL].[dbo].[_INV_ProductCombinationAttributes]
Where Size LIKE '%[^0-9]%' and [StockQuantity]>0
Group by [ProductVariantId]
order by Total Desc) as yüzde
FROM [Live_ADL].[dbo].[_INV_ProductCombinationAttributes]
Where Size LIKE '%[^0-9]%' and [StockQuantity]>0
group by [ProductVariantId]
order by yüzde desc
you don't really need a SP, you can do it in-line, using CTE for instance, something along these lines:
; with tabyuzde as
(
SELECT [ProductVariantId] ,
count([ProductVariantId]) as bedensayısı,
count([ProductVariantId]) * 100.0 / (SELECT Top 1 Count(*) as Total
FROM [Live_ADL].[dbo].[_INV_ProductCombinationAttributes]
Where Size LIKE '%[^0-9]%' and [StockQuantity]>0
Group by [ProductVariantId]
order by Total Desc) as yüzde
FROM [Live_ADL].[dbo].[_INV_ProductCombinationAttributes]
Where Size LIKE '%[^0-9]%' and [StockQuantity]>0
group by [ProductVariantId]
)
update x
set othertablevalue=yüzde
from
othertable x
join tabyuzde t on x.ProductVariantId=t.ProductVariantId
i am trying to run an export on a system that only allows t-sql. i know enough of php to make a foreach loop, but i don't know enough of t-sql to generate multiple rows for a given quantity.
i need a result to make a list of items with "1 of 4" like data included in the result
given a table like
orderid, product, quantity
1000,ball,3
1001,bike,4
1002,hat,2
how do i get a select query result like:
orderid, item_num, total_items,
product
1000,1,3,ball
1000,2,3,ball
1000,3,3,ball
1001,1,4,bike
1001,2,4,bike
1001,3,4,bike
1001,4,4,bike
1002,1,2,hat
1002,2,2,hat
You can do this with the aid of an auxiliary numbers table.
;WITH T(orderid, product, quantity) AS
(
select 1000,'ball',3 union all
select 1001,'bike',4 union all
select 1002,'hat',2
)
SELECT orderid, number as item_num, quantity as total_items, product
FROM T
JOIN master..spt_values on number> 0 and number <= quantity
where type='P'
NB: The code above uses the master..spt_values table - this is just for demo purposes I suggest you create your own tally table using one of the techniques here.
If you are on SQL Server 2005 or later version, then you can try a recursive CTE instead of a tally table.
;WITH CTE AS
(
SELECT orderid, 1 item_num, product, quantity
FROM YourTable
UNION ALL
SELECT orderid, item_num+1, product, quantity
FROM CTE
WHERE item_num < quantity
)
SELECT *
FROM CTE
OPTION (MAXRECURSION 0)
I'm not on a computer with a database engine where I can test this, so let me know how it goes.
Well, IF you know the maximum value for the # of products for any product (and it's not too big, say 4), you can:
Create a helper table called Nums containing 1 integer column n, with rows containing 1,2,3,4
Run
SELECT * from Your_table, Nums
WHERE Nums.n <= Your_table.quantity