It is actually possible to use # (the at sign) with sqlite to be able to use a calculated value as a constant in an other query ?
I am using a variable(a total) that i calculated previously to get an other variable (a proportion) over two time periods.
Total amout of sale
Proportion of sale between the first semester and second semester.
I copy the first query to get the constant and i had the first query to the second.
The answer is no BUT:-
This could possibly be done in a single query.
Consider this simple demo with hopefully easy to understand all-in-one queries:-
First the sales table:-
i.e. 2 columns semester and amount
10 rows in total so 1000 is the total amount
6 rows are S1 (amount is 600) so 60%
4 rows are S2 (amount is 400) so 40%
Created and populated using:-
CREATE TABLE IF NOT EXISTS sales (semester TEXT, amount REAL);
INSERT INTO sales VALUES('S1',100),('S1',100),('S1',100),('S1',100),('S1',100),('S1',100),('S2',100),('S2',100),('S2',100),('S2',100);
So you could use an all-in-one query such as:-
SELECT
(SELECT sum(amount) FROM sales) AS total,
(SELECT sum(amount) FROM sales WHERE semester = 'S1') AS s1total,
((SELECT sum(amount) FROM sales WHERE semester = 'S1') / (SELECT sum(amount) FROM sales)) * 100 AS s1prop,
(SELECT sum(amount) FROM sales WHERE semester = 'S2') AS s2total,
((SELECT sum(amount) FROM sales WHERE semester = 'S2') / (SELECT sum(amount) FROM sales)) * 100 AS s2prop
;
This would result in
i.e. s1prop and s2prop the expected results (the other columns may be useful)
An alternative, using a CTE (Common Table Expressions) that does the same could be:-
WITH cte_total(total,s1total,s2total) AS (SELECT
(SELECT sum(amount) FROM sales),
(SELECT sum(amount) FROM sales WHERE semester = 'S1'),
(SELECT sum(amount) FROM sales WHERE semester = 'S2')
)
SELECT total, s1total, (s1total / total) * 100 AS s1prop, s2total, (s2total / total) * 100 AS s2prop FROM cte_total;
you can have multiple CTE's and gather data from other tables or even being passed as parameters. They can be extremely useful and would even allow values to be accessed throughout.
e.g.
Here's an example where a 2nd cte is added (as the first cte) that mimics passing 3 dates (instead of the hard coded values ?'s could be coded and the parameters passed via parameter binding).
As the sales table has no date for the sale a literal value has been coded, this would be normally be the column with the sale date instead of WHERE '2023-01-01' /*<<<<< would be the column that holds the date */
the hard coded date has purposefully been used so result in the BETWEEN clause resulting in true.
if the date column did exist then WHERE criteria for the semester could then be by between the respective dates for the semester.
The example:-
WITH
dates AS (SELECT
'2023-01-01' /*<<<<< ? and can then be passed as bound parameter*/ AS startdate,
'2023-03-01' /*<<<<< ? and can then be passed as bound parameter*/ AS semester2_start,
'2023-05-30' /*<<<<< ? and can then be passed as bound parameter*/as enddate
),
cte_total(total,s1total,s2total) AS (SELECT
(SELECT sum(amount) FROM sales
WHERE '2023-01-01' /*<<<<< would be the column that holds the date */
BETWEEN (SELECT startdate FROM dates)
AND (SELECT enddate FROM dates)),
(SELECT sum(amount) FROM sales WHERE semester = 'S1'),
(SELECT sum(amount) FROM sales WHERE semester = 'S2')
)
SELECT total, s1total, (s1total / total) * 100 AS s1prop, s2total, (s2total / total) * 100 AS s2prop FROM cte_total;
SELECT a_offer.name as Engagement Name, count(*) count
FROM u_user_offer_detail_record
left join a_offer on a_offer.id = u_user_offer_detail_record.offer_id
WHERE 1
and update_time_ms>= UNIX_TIMESTAMP([[{{start_date}} #]] date(Now()-Interval 1 DAY)) * 1000
and update_time_ms<= UNIX_TIMESTAMP([[{{end_date}} #]] Now()) * 1000
and award_status=12
and u_user_offer_detail_record.adset_id = [[{{adset_id}} #]]1459904136457728
group by a_offer.name
I want to user datetime picker, if not use default date, but it can't work when select date, How can I do?
order by count desc)
My virtual radar program maintains a SQLite3 database. In the database are 2 tables, Aircraft and Flights. The first stores aircraft data and the other flights a particular aircraft made.
I'd like to get a list of aircraft that do not have a flight in the last 180 days.
Reading on the Internet I could create this query:
SELECT Registration,
STRFTIME('%d-%m-%Y',Flights.EndTime) AS 'Last Flight',
Flights.Callsign,
CAST ((JULIANDAY('now') - JULIANDAY(Flights.EndTime)) AS INTEGER) AS
'Days unseen'
FROM Aircraft
INNER JOIN Flights ON (Aircraft.AircraftID=Flights.AircraftID)
WHERE
CAST ((JULIANDAY('now') - JULIANDAY(Flights.EndTime))AS INTEGER) >= 180
GROUP BY Registration
ORDER BY Flights.EndTime
The problem is that the Flights.EndTime is written in ascending order and the query thus looks at the first Flights.EndTime entry instead of the last one.
Is it possible to query the database and retrieve the list of aircraft that were not seen for 180 days or more?
With this query:
SELECT *, ROW_NUMBER() OVER (PARTITION BY AircraftID ORDER BY EndTime DESC) rn
FROM Flights
you can rank all the flights of each aircraft by EndTime descending.
If you join the above query to Aircraft and filter only the last flight (row number = 1), then there is no need for GROUP BY:
SELECT a.Registration,
STRFTIME('%d-%m-%Y', f.EndTime) AS `Last Flight`,
f.Callsign,
CAST(JULIANDAY('now') - JULIANDAY(f.EndTime) AS INTEGER) AS `Days unseen`
FROM Aircraft a
INNER JOIN (
SELECT *, ROW_NUMBER() OVER (PARTITION BY AircraftID ORDER BY EndTime DESC) rn
FROM Flights
) f ON a.AircraftID = f.AircraftID
WHERE f.rn = 1 AND CAST(JULIANDAY('now') - JULIANDAY(f.EndTime) AS INTEGER) >= 180
ORDER BY f.EndTime
I'm looking to improve this query I wrote for a small web application in ASP.NET 4.0 using SQL-Server 2005. This application will allow the user to search by Product ID and have it return the following information:
Highest Purchase Price + Most Recent Date of purchase # this price
Lowest Purchase Price + Most Recent Date of purchase # this price
Most Recent Purchase Price + Date
Average Purchase Price (optional, i thought this might improve the usefulness of the app)
Here is the structure of the Products table (I'm only including relevant columns, this is a DB already in production and these are non-pk columns)
product_id (nvarchar(20))
price (decimal(19,2))
pDate (datetime)
Before I put down the query I have so far I just want to say that I can get this information easily through multiple queries, so if this is the best practice then disregard improving the query, but I was aiming to minimize the number of queries needed to get all needed information.
What I have so far: (Note: There are rows with price = 0 so I ignored those in the bottom select looking for the MIN price)
SELECT price, MAX(pDate)
FROM Products
WHERE product_id = #product_id AND
(price = (SELECT MAX(price)
FROM Products
WHERE product_id =#product_id) OR
price = (SELECT MIN(price)
FROM Products
WHERE product_id = #product_id AND price > 0))
GROUP BY price
Now this is returning 2 rows:
first = the lowest price + date
second row = high price + date
What I would like ideally is to have a query return 1 row with all the needed information stated above if possible, as it would simplify displaying the information in ASP for me. And like I said earlier, if multiple queries is the be approach then no need to re-write a complex query here.
Edit
Here is some sample data
Desired query results: (ignore the format as I typed this in excel)
Here is the query I will be using thanks to Ken Benson:
SELECT TOP 1 prod.product_id,
minp.price AS minprice, minp.pDate as minlastdate,
maxp.price AS maxprice, maxp.pDate as maxlastdate,
ag.price AS averageprice
FROM products AS prod
LEFT JOIN (SELECT lmd.product_id,max(lmd.pDate) as pDate,mn.price FROM products as lmd INNER JOIN
(SELECT product_id, min(price) AS price from products WHERE price > 0 group by product_id) as mn ON lmd.product_id=mn.product_id AND lmd.price=mn.price
group by lmd.product_id,mn.price ) AS minp ON minp.product_id=prod.product_id
LEFT JOIN (SELECT lxd.product_id,max(lxd.pDate) as pDate,mx.price FROM products as lxd INNER JOIN
(SELECT product_id, max(price) AS price from products group by product_id) as mx ON lxd.product_id=mx.product_id AND lxd.price=mx.price
group by lxd.product_id,mx.price ) AS maxp ON maxp.product_id=prod.product_id
LEFT JOIN (SELECT product_id,avg(price) as price FROM products WHERE price > 0 GROUP BY product_id) AS ag ON ag.product_id=prod.product_id
WHERE prod.product_id=#product_id
I think you can do a couple of joins back to the table ...
Select product_id, min.price, min.pDate, max.price, max.pDate
FROM products as p
LEFT JOIN (Select Min(price), pDate, product_id FROM products GROUP BY product_id)
as min on min.product_id=p.product_id
LEFT JOIN (Select max(price), pDate, product_id FROM products GROUP BY product_id)
as max on max.product_id=p.product_id
Where p.product_id = #product_id
This second bit of code should produce desired results....
SELECT prod.product_id,
minp.price AS minprice, minp.pDate as minlastdate,
maxp.price AS maxprice, maxp.pDate as maxlastdate,
ag.price AS averageprice
FROM products AS prod
LEFT JOIN (SELECT lmd.product_id,max(lmd.pDate) as pDate,mn.price FROM products as lmd INNER JOIN
(SELECT product_id, min(price) AS price from products group by product_id) as mn ON lmd.product_id=mn.product_id
group by lmd.product_id,mn.price ) AS minp ON minp.product_id=prod.product_id
LEFT JOIN (SELECT lxd.product_id,max(lxd.pDate) as pDate,mx.price FROM products as lxd INNER JOIN
(SELECT product_id, max(price) AS price from products group by product_id) as mx ON lxd.product_id=mx.product_id
group by lxd.product_id,mx.price ) AS maxp ON maxp.product_id=prod.product_id
LEFT JOIN (SELECT product_id,avg(price) as price FROM products GROUP BY product_id) AS ag ON ag.product_id=prod.product_id
WHERE prod.product_id=1
LIMIT 1
Yep - left out an 'and' condition:
SELECT TOP 1
prod.product_id,
minp.price AS minprice, minp.pDate as minlastdate,
maxp.price AS maxprice, maxp.pDate as maxlastdate,
ag.price AS averageprice
FROM products AS prod
LEFT JOIN (SELECT lmd.product_id,max(lmd.pDate) as pDate,mn.price FROM products as lmd INNER JOIN
(SELECT product_id, min(price) AS price from products group by product_id) as mn ON lmd.product_id=mn.product_id **AND lmd.price=mn.price**
group by lmd.product_id,mn.price ) AS minp ON minp.product_id=prod.product_id
LEFT JOIN (SELECT lxd.product_id,max(lxd.pDate) as pDate,mx.price FROM products as lxd INNER JOIN
(SELECT product_id, max(price) AS price from products group by product_id) as mx ON lxd.product_id=mx.product_id AND **lxd.price=mx.price**
group by lxd.product_id,mx.price ) AS maxp ON maxp.product_id=prod.product_id
LEFT JOIN (SELECT product_id,avg(price) as price FROM products GROUP BY product_id) AS ag ON ag.product_id=prod.product_id
WHERE prod.product_id=#product_id
I would do this with a combination of ranking functions and conditional aggregations:
select product_id,
max(case when seqnum_hi = 1 then price end) as highPrice,
max(case when seqnum_hi = 1 then pdate end) as highPrice_date
max(case when seqnum_low = 1 then price end) as lowPrice,
max(case when seqnum_low = 1 then pdate end) as lowPrice_date,
max(case when seqnum_rec = 1 then price end) as recentPrice,
max(case when seqnum_rec = 1 then pdate end) as recentPrice_date,
avg(price) as avg_price
from (select p.*,
row_number() over (partition by product_id order by price asc) as seqnum_low,
row_number() over (partition by product_id order by price desc) as seqnum_hi,
row_number() over (partition by product_id order by pdate desc) as seqnum_rec
from price
where product_id = #product_id
group by product_id
The seguence numbers identify the rows with the particular attributes you care about (high price, low price, most recent). The conditional max then just selects information from those rows.
The following should get what you want. It's pretty long, but is readable so should be easily modified by anyone who needs to:
;WITH CTE_MaxPrice AS
(
SELECT product_id, MAX(P.price) AS MaxPrice
FROM Products P
GROUP BY product_id
HAVING product_id = #product_id
),
CTE_MinPrice AS
(
SELECT product_id, MIN(P.price) AS MinPrice
FROM Products P
GROUP BY product_id
HAVING product_id = #product_id
),
CTE_MaxPriceDate AS
(
SELECT P.product_id, MAX(P.pDate) AS MaxDate
FROM Products P
INNER JOIN CTE_MaxPrice MaxP ON P.product_id = MaxP.product_id
AND P.price = MaxP.MaxPrice
GROUP BY P.product_id
),
CTE_MinPriceDate AS
(
SELECT P.product_id, MAX(P.pDate) AS MinDate
FROM Products P
INNER JOIN CTE_MinPrice MinP ON P.product_id = MinP.product_id
AND P.price = MinP.MinPrice
GROUP BY P.product_id
)
SELECT MaxP.MaxPrice, MaxPD.MaxDate,
MinP.MinPrice, MinPD.MinDate,
RP.price AS RecentPrice, MAX(RP.pDate) AS RecentDate,
AVG(AP.price) AS AveragePrice
FROM Products P
INNER JOIN CTE_MaxPrice MaxP ON P.product_id = MaxP.product_id
INNER JOIN CTE_MinPrice MinP ON P.product_id = MinP.product_id
AND MinP.MinPrice > 0
INNER JOIN CTE_MaxPriceDate MaxPD ON P.product_id = MaxPD.product_id
INNER JOIN CTE_MinPriceDate MinPD ON P.product_id = MinPD.product_id
INNER JOIN Products RP ON P.product_id = RP.product_id
INNER JOIN Products AP ON P.product_id = AP.product_id
GROUP BY MaxP.MaxPrice, MaxPD.MaxDate,
MinP.MinPrice, MinPD.MinDate, RP.price
HAVING P.product_id = #product_id
Well since there have been three attempts to answer, and none have worked quite how you want, I'll tell you how I would do it - and this assumes you can use a stored procedure and also assumes that the product table is not so huge that multiple seperate queries would be a problem:
CREATE PROCEDURE myproc AS
DECLARE #Price1 money
DECLARE #Date1 smalldatetime
DECLARE #Price2 money
DECLARE #Date2 smalldatetime
DECLARE #Price3 money
DECLARE #Date3 smalldatetime
DECLARE #Price4 money
SELECT #Price1 = MAX(Price) FROM Products
SELECT #Date1 = MAX(pDate) FROM Products WHERE Price=#Price1
SELECT #Price2 = Min(Price) FROM Products WHERE Price >0
SELECT #Date2 = MAX(pDate) FROM Products WHERE Price=#Price2
SELECT #Date3 = Max(pDate) FROM Products
SELECT #Price3 = MAX(Price) FROM Products WHERE pDate=#Date3 --max in case there are more than one purchases with the same date.
SELECT #Price4 = AVG(Price) FROM Products WHERE Price>0
SELECT #Price1 As MaxPrice,
#Date1 As MaxPriceDate,
#Price2 As LowPrice,
#Date2 As LowPriceDate,
#Price4 As AveragePrice,
#Price3 As RecentPrice,
#Price3 As RecentPriceDate
GO
Forgive any typographical errors, I didn't test this, but if you can use stored procedures, this will work.
So this is not much different than doing your multiple queries from the client, but should perform better putting them all into a single SP. You could also cut the number of queries down a bit by using some of the code from your other answers, but I have left it this way for clarity.
SELECT gameratingstblx245v.gameid,avg( gameratingstblx245v.rating ) as avgrating, count(gameratingstblx245v.rating) as count,gamedata.name ,gamedata.gameinfo
FROM gameratingstblx245v
LEFT JOIN gamedata ON gamedata.id = gameratingstblx245v.game_id
WHERE gameratingstblx245v.game_id=gameratingstblx245v.game_id
GROUP BY gameid
ORDER BY avg( gameratingstblx245v.rating ) DESC LIMIT 0,8
Table gameratingstblx245v - gameid, rating
Rable gamedata - id, gameinfo, name, releasedate
This is the query I am currently using to extract data from two tables gamedata and gameratingstblx245v.... What I am doing here is taking the avg. of all the ratings from table gameratingstblx245v in descending order of their avg. rating and I am also extracting the related info corresponding to the selected gameid's from table gamedata...
Now what I want to extract is the top avg. ratings from game_ratingstblx245v but for the games whose field releasedate from table gamedata is in the last 90 days...
Help would be appreciated..Thanks
Here's how I'd design that query:
SELECT d.id, d.name, d.gameinfo,
AVG(r.rating) AS avgrating, COUNT(r.rating) AS count
FROM gamedata d
LEFT JOIN gameratingstblx245v r ON (d.id = r.game_id)
WHERE d.releasedate BETWEEN NOW() - INTERVAL 90 DAY AND NOW()
GROUP BY d.id
ORDER BY avgrating DESC LIMIT 0,8;