my products table :
ProductId(inc.key) | Price | VersionCreatedDate | MainProductId
1 | 15 | 1-11-2016 | 1
2 | 20 | 1-11-2016 | 2
3 | 30 | 1-11-2016 | 3
4 | 10 | 2-11-2016 | 1 -> mainProductId 1 changed price(-5$)
5 | 20 | 3-11-2016 | 3 -> mainProductId 3 changed price(-10$)
6 | 30 | 4-11-2016 | 3 -> mainProductId 3 changed price(+10$)
I want to display the output as like this
Date | AvgPrice
1-11-2016 | 21.67 ((15+20+30)/3)
2-11-2016 | 20 ((10+20+30)/3)
3-11-2016 | 16.67 ((10+20+20)/3)
4-11-2016 | 20 ((10+20+30)/3)
How do I get the output with sql code?
Assuming you have a calendar table with all dates you need. And you have a main_products table with MainProductId as primary/unique key. The following query should return average prices for every day in october 2016.
select sub.date, avg(sub.Price) as Price
from (
select
c.date,
m.MainProductId,
(
select p.Price
from products
where p.MainProductId = m.MainProductId
and p.VersionCreatedDate < c.date + interval 1 day
order by p.VersionCreatedDate desc
limit 1
) as Price
from callendar c
cross join main_products m
where c.date between '2016-10-01' and '2016-10-31'
) sub
group by sub.date
order by sub.date
The subquery (derived table aliased as sub) returns a combination of all dates in the range and all "main products" from the main_products table. The recent price each "main product" for a specific date is calculated in the subselect (correlated subquery in the SELECT clause) using ORDER BY and LIMIT 1. This allows us to group the subquery result by date and calculate the average price per date.
It is even possible to eliminate the derived table and hope that mysql can use an index to GROUP BY date instead of working on a temp table:
select c.date, avg((
select p.Price
from products
where p.MainProductId = m.MainProductId
and p.VersionCreatedDate < c.date + interval 1 day
order by p.VersionCreatedDate desc
limit 1
)) as Price
from callendar c
cross join main_products m
where c.date between '2016-10-01' and '2016-10-31'
group by c.date
order by c.date
I have no clue if that query can be executed effiently (especially if mysql can). You should however have at least the following indexes: callendar(date), products(MainProductId, VersionCreatedDate)
Related
I'm trying to select rows in which 3+ posts is in the interval 14 days.
For example:
User | id_post | date
1 | 12 | 2018-01-01
1 | 13 | 2018-01-05
1 | 14 | 2018-01-21
1 | 15 | 2018-01-27
1 | 16 | 2018-01-29
2 | 17 | 2018-01-01
2 | 18 | 2018-01-20
2 | 19 | 2018-02-17
2 | 20 | 2018-03-07
2 | 21 | 2018-04-29
User = OwnerUserId
date = CreationDate
In this case I need to return just User 1 because he has posts which are in 14 days.
Please, help me how I can get it. Thank you
Update: A user should have posts which were published in the interval of 14 days. It can be more, for example if the last day is in 2019 but in 2018 there was 3posts published within 14 days - it's ok
now i have (data get from data.stackexchange stackoverflow) and tried to apply
select OwnerUserId from Posts as p
where OwnerUserId in (select Users.id from Users WHERE YEAR (Users.CreationDate) >= 2017)
AND YEAR (p.CreationDate) >= 2018
AND p.Tags like '%sql%'
join (select OwnerUserId, CreationDate as startdate, dateadd(day,14,CreationDate) as enddate
from Posts) as r
on p.OwnerUserId = r.OwnerUserId and p.CreationDate between r.startdate and r.enddate
group by p.OwnerUserId, CreationDate
having count(*) >= 3
but it replies
Incorrect syntax near the keyword 'join'.
Incorrect syntax near the keyword 'as'.
I'm a begginner here and in the sql, so i dont exactly know how to combine my previous 'filtr' and current join with date
I'll not tell you the solution, but give you some pseudo-code and you figure out how to code it in SQL-
a) You should restrict your data for just 14 days.
b) Now, make groupings by User and find the count of records/lines present (for each User).
c) Now, again do a filter check to find users whose count of records is greater than 3.
Now, tell us which SQL keywords will be used for each points above.
I think something like
select p.user_id
from posts p
join (select user_id, xdate start_date, date_add(xdate, interval 14 day) end_date
from posts) r
on p.user_id = r.user_id and p.xdate between r.start_date and r.end_date
group by user_id, start_date
having count(*) >= 3
can help. It may not be the best possible solution, but it works.
Check it on SQL Fiddle
If you just want to select users by id you may try
Select id_post, date from yourtable where user = 2 order by id DESC limit 10;
You should have Colum called id with auto increment so new posts will have higher id so when it's sorted in descending it will start with post with higher id also you should have index on that id colum auto increment and index
If you don't want to use the above method then you will do that with date range like this
$date = gmdate() - (3600*24); 24 is 24 hours past
Select id_post, title from mutable where add_date > 'value of $date'
In both cases you should have index on user id
The second query is what you need but you should get the date from the equation first then apply it to the query
First, I think you mean user 1 not 2.
In MySQL 8+, this is pretty easy. If you want the first such post:
select t.*
from (select t.*,
lead(date, 2) over (partition by user order by date) as next_date2
from t
) t
where next_date2 <= date + interval 14 day;
So I have following data in a product_rate_history table -
I want to select last N records ( eg 7 records ) informing rate change history of given product. If product rate is changed more than one time a day, then query should select most recent rate change for that day.
So from above table I want output like following for product id 16-
+-----------+-------------------------+------------------------+
| product_id | previous_rate | date |
+----------------+--------------------+------------------------|
| 16 | 2400 | 2016-04-30 23:05:35 |
| 16 | 4500 | 2016-04-29 11:02:42 |
+----------------+--------------------+------------------------+
I have tried following query but it returns only one row having last update rate only-
SELECT * FROM `product_rate_history` prh
INNER JOIN (SELECT max(created_on) as max FROM `product_rate_history` GROUP BY Date(created_on)) prh2
ON prh.created_on = prh2.max
WHERE prh.product_id = 16
GROUP BY DATE(prh.created_on)
ORDER BY prh.created_on DESC;
First, you do not need an aggregation in the outer query.
Second, you need to repeat the WHERE clause in the subquery (for the method you are using):
SELECT prh.*
FROM product_rate_history prh INNER JOIN
(SELECT max(created_on) as maxco
FROM product_rate_history
WHERE prh.product_id = 16
GROUP BY Date(created_on)
) prh2
ON prh.created_on = prh2.maxco
WHERE prh.product_id = 16
ORDER BY prh.created_on DESC;
I am trying to generate a table in the following format.
Proday | 2014-04-01 | 2014-03-01
--------------------------------
1 | 12 | 17
2 | 6 | 0
7 | 0 | 24
13 | 3 | 7
Prodays (duration between two timestamps) is a calculated value and the data for months is a COUNT. I can output the data for a single month, but am having troubles joining queries to additional months. The index (prodays) may not match for each month. e.g.. 2014-04-01 may not have any data for Prodays 7, whereas 2014-03-01 may not have Proday 2. Should indicate with 0 or null.
I suspect FULL OUTER JOIN is what should do the trick. But have read that's not possible in Mysql?
This is the query to get data for a single month:
SELECT round((protime - createtime) / 86400) AS prodays, COUNT(id) AS '2014-04-01'
FROM `tbl_users` as t1
WHERE status = 1 AND DATE_FORMAT(FROM_UNIXTIME(createtime),'%Y-%m-%d') >= '2014-04-01'
AND DATE_FORMAT(FROM_UNIXTIME(createtime),'%Y-%m-%d') <= LAST_DAY('2014-04-01')
GROUP BY prodays
ORDER BY `prodays` ASC
How can I join/union an additional query to create a column for 2014-03-01?
You want to use conditional aggregation -- that is, move the filtering logic from the where clause to the select clause:
SELECT round((protime - createtime) / 86400) AS prodays,
sum(DATE_FORMAT(FROM_UNIXTIME(createtime),'%Y-%m-%d') >= '2014-04-01' AND
DATE_FORMAT(FROM_UNIXTIME(createtime),'%Y-%m-%d') <= LAST_DAY('2014-04-01')
) as `2014-04-01`,
sum(DATE_FORMAT(FROM_UNIXTIME(createtime),'%Y-%m-%d') >= '2014-03-01' AND
DATE_FORMAT(FROM_UNIXTIME(createtime),'%Y-%m-%d') <= LAST_DAY('2014-03-01')
) as `2014-03-01`
FROM `tbl_users` as t1
WHERE status = 1
GROUP BY prodays
ORDER BY `prodays` ASC;
i have a table main:
(
time date,
qty int
)
i want to create a query so for each day i get the sum of qty on that day and all days before that
so for this data
-----------------------
time | qty
01/09/2009 | 3
02/09/2009 | 8
03/09/2009 | 2
04/09/2009 | 5
i get:
-----------------------
time | total
01/09/2009 | 3
02/09/2009 | 11
03/09/2009 | 13
04/09/2009 | 18
thanks in advance
This should give you a faster result
SELECT time
, #tot_qty := #tot_qty+qty AS tot_qty
FROM Table1
JOIN (SELECT #tot_qty := 0) d
order by time
SQL FIDDLE
SELECT
M.Time,
SUM(M2.Qty) RunningTotal
FROM
Main M
LEFT JOIN Main M2 ON M.Time >= M2.Time
GROUP BY
M.Time;
SELECT TIME, (SELECT SUM(QTY) FROM main m2 WHERE m2.ITME <= mt1.TIME) AS sum
FROM main m1
ORDER BY TIME
This should do the trick, though it might not be the fastest solution.
I've been searching for answers for 2 day and still nothing. Please, help me.
I have a database with products, product's prices and the date when this prices were registered:
product_id | price | date
-------------------------
1 | 8.95 | 2012-12-01
2 | 3.40 | 2012-12-01
1 | 9.05 | 2012-12-19
3 | 2.34 | 2012-12-24
3 | 2.15 | 2012-12-01
1 | 8.80 | 2012-12-19
1 | 8.99 | 2012-12-02
2 | 3.45 | 2012-12-02
Observe that is possible to have different price values for a product on the same day (rows 3 and 6). This is because there are many suppliers for a single product. There is a supplier column on database too, but I found it irrelevant for the solution. You can add it to the solution if I'm wrong.
Basically what I want is to write a query that returns two combined sets of data, as follow:
First set is made by minimum price of products inserted in the last month. As today is jan, 15, query should read rows 3, 4 and 6, apply the minimum price, and return only rows 4 and 6, both with minimum price for that product on the last month.
Second set is made by last products inserted, with no price registered on last month. i.e, for products not shown in the first set, query should search for the last inserted ones.
I hope that is clear. Ask me more if it isn't.
The query result for this database should be:
product_id | price | date
-------------------------
1 | 8.80 | 2012-12-19 <-Min price for product 1 on last month
3 | 2.34 | 2012-12-24 <-Min price for product 3 on last month
2 | 3.45 | 2012-12-02 <-No reg for product 2 on last month, show last reg.
I've tried everything: UNION, (DATE_SUB(CURDATE(), INTERVAL 1 MONTH), MIN(price), MAX(date) etc, etc. Nothing works. I don't know where to search now, please help me.
(SELECT product_id, MIN(price), date
FROM products
WHERE date + INTERVAL 1 MONTH > NOW()
GROUP BY product_id)
UNION
(SELECT product_id, price, MAX(date)
FROM products
WHERE product_id NOT IN (SELECT product_id
FROM products
WHERE date + INTERVAL 1 MONTH > NOW()
GROUP BY product_id)
GROUP BY product_id)
This should work but I'm not sure it's the most optimized way to do it.
something like this will do the trick:
SELECT * FROM (
SELECT DISTINCT b.product_id, IF (c.min IS NULL,(SELECT ROUND(e.price,2) FROM products AS e WHERE e.product_id = b.product_id ORDER BY e.date DESC LIMIT 1 ),c.min) AS min, IF (c.date IS NULL,(SELECT f.date FROM products AS f WHERE f.product_id = b.product_id ORDER BY f.date DESC LIMIT 1 ),c.date) AS date, IF(c.min IS NULL,'<-No reg for product 2 on last month, show last reg.','<-Min price for product 1 on last month') as text FROM products AS b
LEFT JOIN
(SELECT a.product_id, round(MIN(a.price),2) AS min, a.date FROM products AS a WHERE a.date BETWEEN DATE_SUB(CURDATE(), INTERVAL 1 MONTH) AND CURDATE() GROUP BY a.product_id) AS c
ON (b.product_id = c.product_id)
) AS d
ORDER BY d.text, d.product_id
Gives output:
product_id|min|date|text
1|8.80|2012-12-19|<-Min price for product 1 on last month
3|2.34|2012-12-24|<-Min price for product 1 on last month
2|3.45|2012-12-02|<-No reg for product 2 on last month, show last reg.
Break it down into several sub-queries:
Products with prices in the last month, min price
join in date for that price
UNION
Products with no-prices in the last month, max date
join in price on that date
SQL Fiddle
Here
Query
SELECT MINPRICE.product_id, P.date, MINPRICE.price
FROM
(
-- Min price in last 31 days
SELECT product_id, MIN(price) AS price
FROM Prices
WHERE DATEDIFF(CURDATE(), date) < 31
GROUP BY product_id
) MINPRICE
-- Join in to get the date that the price occured on
INNER JOIN Prices P ON
P.product_id = MINPRICE.product_id
AND
P.price = MINPRICE.price
UNION
SELECT MAXDATE.product_id, MAXDATE.date, P.price
FROM
(
-- Product with no price in last 31 days - get most recent date
SELECT product_id, MAX(date) AS date
FROM Prices
WHERE product_id NOT IN
(
SELECT product_id
FROM Prices
WHERE DATEDIFF(CURDATE(), date) < 31
)
) MAXDATE
-- join in price on that date
INNER JOIN Prices P ON
P.product_id = MAXDATE.product_id
AND
P.date = MAXDATE.date
Not that I tested but you can try...
SELECT * FROM
(SELECT * FROM (
SELECT * FROM table ORDER BY date DESC)
as tmp GROUP BY product_id) t1
LEFT JOIN
(SELECT * FROM (
SELECT * FROM table WHERE date => CURDATE() ORDER BY price)
as tmp2 GROUP BY product_id) t2
ON t1.product_id = t2.product_id