MYSQL Recursive query with conditions - mysql

I have 2 tables,
the first table contains id_product, its rate and its price.
ID_product
rate
Price
1
TSA1
0.12
2
TSA1
1.5
1
TSA2
0.14
2
TSA2
1.7
1
TSA3
NULL
2
TSA3
1.7
1
TASM4
1.68
I have an other table which contains a rate and its rate destination if the price for its rate is NULL. Its for always has a price for each product. Here for example, the product 1 doesnt have a price for the rate TSA3. The correspondance table says that if it doesnt have a price for this rate, use the price of TASM4.
Origin_rate
Destination_rate
TSA1
TAS2
TSA2
TAS3
TSA3
TASM4
So, How can I complete my first table? I think, i need a recursive query, but i dont know how to do it in SQL.

This query gets you the price hirarchically:
with recursive cte(id_product, rate, price, origin_rate) as
(
select id_product, rate, price, rate
from mytable
union all
select cte.id_product, cte.rate, t.price, t.rate
from cte
join map on map.origin_rate = cte.origin_rate
left join mytable t on t.id_product = cte.id_product
and t.rate = map.destination_rate
where cte.price is null
)
select id_product, rate, price
from cte
where price is not null
order by id_product, rate;

Related

Get sum of values for multiple categories for a given list of dates

I need to write a query to get the sum of values for each category for a list of given dates. If a value doesn't exist for a category, we should get the value from the previous date. Basically something like "max per category per date". The end goal is a trend chart. If a previous value for a category doesn't exist, setting the value to 0 is fine.
See tables and result below:
Category
id
name
1
savings
2
cash
3
stocks
Item
id
categoryId
value
createdAt
1
1
100
2022-01-01
2
2
20
2022-01-01
3
3
500
2022-01-01
4
2
0
2022-01-02
5
3
1000
2022-01-03
Result
createdAt
total
2022-01-01
620
2022-02-02
600
2022-02-03
1100
To get a result for a single date I could do something like this:
SELECT SUM(value) as total
FROM Category
LEFT JOIN (
SELECT id, categoryId, value
FROM Item
WHERE id IN (
SELECT MAX(id) FROM Item WHERE createdAt <= '2022-01-10' GROUP BY categoryId)
) items ON Category.id = items.categoryId;
I have absolutely no clue on how to approach doing this for multiple dates, eg. if my input would be every day in the month of January 2022. I'm running on MySQL 8.0.23. Also, if this is not feasible with a single query, I'm up for ideas. Do you have any suggestions?
Try this:
with u as
(select id as categoryId from Category),
v as
(select distinct createdAt from Item),
w as
(select * from u cross join v),
x as
(select createdAt,
categoryId,
(select value
from Item
where categoryId = w.categoryId and createdAt <= w.createdAt
order by createdAt desc
limit 1) as value
from w)
select createdAt, sum(value) as total
from x
group by createdAt
Basically getting all the combinations of the creation dates with the categoryIds, then using a subquery to get the value of the closest or equal date for each categoryId.
A Fiddle.
One option uses window functions such as SUM() OVER () and LAG() such as
WITH i AS
(
SELECT SUM(`value`) OVER (PARTITION BY `createdAt`,`categoryId` ORDER BY `createdAt`) AS total_sofar,
LAG(`value`,1,0) OVER (PARTITION BY `categoryId` ORDER BY `createdAt`) AS lg,
`createdAt`
FROM Item
)
SELECT DISTINCT `createdAt`,
SUM(total_sofar) OVER (ORDER BY `createdAt`)-SUM(lg) OVER (ORDER BY `createdAt`) AS total
FROM i
ORDER BY `createdAt`
as you have MySQL DBMS of version 8.0. The trick is grouping(partitioning by categoryId along with the LAG at the first query)
Demo

MySQL Query to calculate average price until stock value reaches 0

I have two MySQL tables which I would like to use but unfortunately this question exceeds my knowledge.
First table shows the stock I have with product ID and Quantity
id PID Quantity
1 5 8
2 45 7
3 125 0
The second table stores my purchase orders I did to purchase the products I have in stock.
id Date PO ID PID Price Purchased Quant.
1 1.1.19 PO1 5 8.00 7
2 1.1.19 PO1 45 2.15 9
3 2.1.19 PO2 5 4.45 6
As a result I would like to get the average price per PID caclulated from the latest purchase date.
PID Average Price
5 5.3375
45 2.15
For PID '5' I have 8pcs in stock and I find 6 pcs purchased on 2.1.19 for 4,45€. Therefore I need to find another 2 pcs in an older purchase which I can find on 1.1.19 for 8.00€.
Average price calculation -> (6pcs * 4.45€ + 2pcs * 8.00€)/8pcs = 5.3375€
For PID 45 the calculation should be the same however my stock is completely fulfilled with the first PO.
Is there any way I can solve this in MySQL with a query.
In versions of MySQL before 8.0 this is not easy to achieve. You can do it with the use of variables that change during the execution of the query, but be aware that there is no documented guarantee that the order of variable assignment is as might be expected.
Now that I have given the disclaimer, here is the query you could use:
select pid,
sum(price * take)/sum(take) avg_price
from (
select pid,
price,
#quantity := if(#pid = pid, #quantity, available) needed,
least(#quantity+0, quantity) take,
#quantity := #quantity - least(#quantity, quantity),
#pid := pid
from (select o.*,
p.quantity available
from orders o
inner join products p
on p.pid = o.pid
order by o.pid,
o.date desc) data,
(select #pid := -1,
#quantity := 0) vars
order by pid, date desc) base
group by pid
fiddle
For a more reliable way, you would better migrate to MySQL where you can use window functions.

mysql - How to calculate mode several times in a table

Im trying to get the mode (the value that appears most often in a set of data) of price for each store in the following table
create table t_products (
store_id int,
product varchar(20),
price int
)
I already have this query which retrieves all the ocurrences of each price in each store
SELECT store_id, price, count(price)
FROM t_products
GROUP BY store_id, price
ORDER BY count(price) DESC;
What else is missing? I was trying to use max() function to get the highest price for each store in several ways with no success.
Thanks in advance
PD this is the result of my current query.
store_id|price|count(price)
2 40 5
1 70 5
2 90 4
3 60 2
1 60 1
3 50 1
3 80 1
1 50 1
I only want to keep
store price
2 40
1 70
3 60
select tmp.store_id, tmp.price from (
SELECT store_id, price
FROM t_products
GROUP BY store_id, price
ORDER BY count(price) DESC
) as tmp
group by tmp.store_id
Good luck )
SELECT store_id, value
FROM (SELECT store_id, value, count(value) c
FROM t_products
GROUP BY store_id, value
ORDER BY count(value) DESC) ds
GROUP BY store_id
HAVING max(ds.c);

How to get rows with max date when grouping in MySQL?

I have a table with prices and dates on product:
id
product
price
date
I create a new record when price change. And I have a table like this:
id product price date
1 1 10 2014-01-01
2 1 20 2014-02-17
3 1 5 2014-03-28
4 2 25 2014-01-05
5 2 12 2014-02-08
6 2 30 2014-03-12
I want to get last price for all products. But when I group with "product", I can't get a price from a row with maximum date.
I can use MAX(), MIN() or COUNT() function in request, but I need a result based on other value.
I want something like this in final:
product price date
1 5 2014-03-28
2 30 2014-03-12
But I don't know how. May be like this:
SELECT product, {price with max date}, {max date}
FROM table
GROUP BY product
Alternatively, you can have subquery to get the latest get for every product and join the result on the table itself to get the other columns.
SELECT a.*
FROM tableName a
INNER JOIN
(
SELECT product, MAX(date) mxdate
FROM tableName
GROUP BY product
) b ON a.product = b.product
AND a.date = b.mxdate
I think the easiest way is a substring_index()/group_concat() trick:
SELECT product,
substring_index(group_concat(price order by date desc), ',', 1) as PriceOnMaxDate
max(date)
FROM table
GROUP BY product;
Another way, that might be more efficient than a group by is:
select p.*
from table t
where not exists (select 1
from table t2
where t2.product = t.product and
t2.date > t.date
);
This says: "Get me all rows from the table where the same product does not have a larger date." That is a fancy way of saying "get me the row with the maximum date for each product."
Note that there is a subtle difference: the second form will return all rows that on the maximum date, if there are duplicates.
Also, for performance an index on table(product, date) is recommended.
You can use a subquery that groups by product and return the maximum date for every product, and join this subquery back to the products table:
SELECT
p.product,
p.price,
p.date
FROM
products p INNER JOIN (
SELECT
product,
MAX(date) AS max_date
FROM
products
GROUP BY
product) m
ON p.product = m.product AND p.date = m.max_date
SELECT
product,
price,
date
FROM
(SELECT
product,
price,
date
FROM table_name ORDER BY date DESC) AS t1
GROUP BY product;

SQL query: calculate profile or loss in given 2 tables

I have 2 tables storing income:
id name date price isDel
1 abc 2012-01-26 613.90 0
2 cde 2012-01-25 530.10 0
and expenses:
id name price date isDel
1 b1 334.90 2012-01-26 0
2 b1 41.90 2012-01-25 0
3 d1 61.90 2012-01-25 0
I would like to get the result as follows:
date total income total expense profile n loss
2012-01-25 530.10 103.80 426.30
2012-01-26 613.90 344.90 26.90
Thanks. Can anyone provide SQL solutions? I did refer some member's question and answer at stackoverflow but I can't modify to want I need. Please help.
Provided you want profit/loss per day this should do:
SELECT Inc.date, TotalInc, TotalExp, TotalInc - TotalExp AS ProfitNLoss
FROM
(
SELECT date, SUM(price) as TotalInc
FROM Income
WHERE isdel = 0
GROUP BY date) as Inc
LEFT OUTER JOIN
(
SELECT date, SUM(price) as TotalExp
FROM Expense
WHERE isdel = 0
GROUP BY date) as Exp
ON Inc.date = Exp.date
UNION
SELECT Exp.date, TotalInc, TotalExp, TotalInc - TotalExp AS ProfitNLoss
FROM
(
SELECT date, SUM(price) as TotalInc
FROM Income
WHERE isdel = 0
GROUP BY date) as Inc
RIGHT OUTER JOIN
(
SELECT date, SUM(price) as TotalExp
FROM Expense
WHERE isdel = 0
GROUP BY date) as Exp
ON Inc.date = Exp.date
Argh, this is "give me the codes" question, but I'll give you few hints:
mySQL GROUP BY tutorial
mySQL GRUOP BY aggregate functions
mySQL subqueries
So what you need to do:
Create list of all unique dates (unfortunately I haven't find a way to generate list of dates within sql without table query or without long php array, if anyone knows a way to do this I'll be glad to add it to anser), so you will have to do this:
SELECT date FROM income GROUP BY date;
-- If there's a chance that you'll have record in expenses and not in income:
(SELECT date FROM income GROUP BY date)
UNION (SELECT date FROM expenses GROUP BY date;)
GROUP BY date;
-- Or create table containing just list of all dates (best option)
And than join all unique dates with expenses and income:
SELECT SUM(expenses.price) AS expenses, SUM(incomes.price) AS income, dates.date
FROM unique_dates -- or from your subquery
LEFT JOIN incomes ON incomes.date = unique_dates.date
LEFT JOIN expenses ON expenses.date = unique_dates.date
GROUP BY unique_dates.date
Oh and I have no idea what does profile n loss mean.
Thanks to Pheiberg and appreciated for your prof reply.
I just did some little change so it will return 0 when table has no record or return NULL, So that Profit calculation still able to cal even given -ve value. Here the code share to u guys.
note: im using MySQL
SELECT Inc.create_dt, IFNULL(TotalInc,0), IFNULL(TotalExp,0), IFNULL(TotalInc,0) - IFNULL(TotalExp,0) AS ProfitNLoss
FROM
(
SELECT create_dt, SUM(price) as TotalInc
FROM income
WHERE IsDel= 0
GROUP BY create_dt) as Inc
LEFT OUTER JOIN
(
SELECT create_dt, SUM(price) as TotalExp
FROM expenses
WHERE IsDel= 0
GROUP BY create_dt) as Exp
ON Inc.create_dt= Exp.create_dt
UNION
SELECT Exp.create_dt, IFNULL(TotalInc,0), IFNULL(TotalExp,0), IFNULL(TotalInc,0) - IFNULL(TotalExp,0) AS ProfitNLoss
FROM
(
SELECT create_dt, SUM(price) as TotalInc
FROM income
WHERE IsDel= 0
GROUP BY create_dt) as Inc
RIGHT OUTER JOIN
(
SELECT create_dt, SUM(price) as TotalExp
FROM expenses
WHERE IsDel= 0
GROUP BY create_dt) as Exp
ON Inc.create_dt= Exp.create_dt