merging two queries - mysql

I have a table of recipes, and I want to show a weekly value for each of them. The values are votes cast for them. My problem is that I want to make an excel-like table with all available fridays on my db, add a column for each recipe, and put it's value for the friday on that column, if any value exists.
Now apparently the easiest join doesn't work so I wrote two queries: one to get all ids for my recipes and one for the values to show. The first (MySql) query is just a select id from recipes, the second is like this:
select d.date,perc from
(SELECT date FROM weekly where YEAR(date)=2014 group by date) as d
left join weekly on d.date = weekly.date and weekly.id_rec= :idrec
Any idea how to merge those two queries? Running two queries makes everything slow down, but when I tried to merge them I didn't get the correct results.
Data:
sql fiddle
The result should be something like:
Dates | Recipe A | Recipe B | ...
Date 1 | 0.005 | 0.11 |
Date 2 | 0 | 0 |
Date 3 | 0 | 0.1 |
Note that Date 2 doesn't exist for Recipe A and B, but for some other do.

You should be able to merge the two queries like this:
SELECT recipes.id, votes.date, votes.perc FROM recipes
RIGHT JOIN
(select weekly.id_rec, d.date, perc from
(SELECT weekly.id_rec, date FROM weekly where YEAR(date) = 2014 group by date) as d left join weekly on d.date = weekly.date) as votes
ON votes.id_rec = recipes.id
SQL Fiddle

Related

SQL Joining query using Selection

I have one table of tbl_order where columns are :
id_order
username
delivery_date etc...
and other table tbl_order_foods where columns are :
id_order
id_food
food_quantity etc
Here the sample pic of tbl_order table
and tbl_order_foods table
Here i am want to select all the foods with quantity with price and unit based on delivery_date.
Ex: Suppose On 2020-04-18 there are 3 orders where foods: tomato's are ordered total 15 kg (3 orders * 5 quantity * food_min_unit_amount * unit) and so on others foods.
how i can get the foodlist of total ordered quantity based on delivery_date
The method you need is the GROUP BY keyword.
SQL grouping works on the given attributes. According to your question this would be the delivery_date. In the projection (the attributes following the SELECT keyword) you then can use attributes you state after the GROUP BY keyword and aggregation functions e.g. SUM and MAX.
Based on your question you could get the total price for all orders on the given date like this:
SELECT order.delivery_date, SUM(food.food_quantity) as amount, SUM(food.food_total_price) as revenue
FROM tbl_order as order
INNER JOIN tbl_order_foods as food ON order.id_order = food.id_order
GROUP BY order.delivery_date
This would result in a list like this:
date | amount | revenue
------------------------
05.01| 10 | 800.00
I don't know whether this is what you wish. If you also want to split it into order positions then you would GROUP BY the food_name as well and add it to the projection which then results in the SUM grouped by the orders on a given day of a given product.
SELECT order.delivery_date, food.food_name, SUM(food.food_quantity) as amount, SUM(food.food_total_price) as revenue
FROM tbl_order as order
INNER JOIN tbl_order_foods as food ON order.id_order = food.id_order
GROUP BY order.delivery_date, food.food_name
Which would result in something like this.
date | food_name | amount | revenue
-----------------------------------
05.01| Tomato | 10 | 800.00
05.01| Apple | 5 | 400.00
Check out GROUP BY with the SUM function, a good article from Tutorialspoint.com is here. The only difference is that you are performing a JOIN to create the resulting table.
SELECT DISTINCT [f.id_food], [o.delivery_date], SUM(f.food_quantity) as [delivered_sum_qty], SUM(f.food_total_price) as [sum_food_total_price]
FROM tbl_order o LEFT JOIN tbl_order_foods f
ON [o.id_order] = [f.id_order]
GROUP BY [o.delivery_date];
If you need it, a pretty clear explanation of how to use JOIN is here as well.

SQL scenario to group a dimension

I am using SQL and here is the scenario I am stuck with
Table A
SubscriptionID | Club | Sum_Of_Billings_Of_All_Month | EventID
Table B:
Cost | EventID
Table A left join Table B on EventID (To track the cost of each subscription)
Result
SubscriptionID | Club | Sum_Of_Billings_Of_All_Month | EventID | Cost
I want to break down the Sum_Of_Billings_Of_All_Month into per day billings. i.e. for each subscription, I want the breakdown of billings per day of the month. For that I will group by Sum_Of_Billings_Of_All_Month instead of subscriptionID.
Consequence
If I group by days of billing, upon joining I will get duplicates of subscriptionIDs and the eventIDs will be duplicated in rows multiple time which will then count the cost multiple times as well.
What I want:
In the same query, I want to be able to group by SubscriptionID so I can keep the unique subscriptions per row with their cost.
But one of the other requirement is that I want to know the breakdown of the billings as well to calculate the breakeven and other metrics in the same query
Here is the actual sample data
Table A
idCustomerSubscription | ClubID | EventId | BillingDate| FinalRevenue
33562784 | 56180001| 5y6m600np1fg | 5/31/2017 | 512
Table B
EventId |Cost
5y6m600np1fg |200
Table A join B left join on eventId (Group by SubscriptionID
idCustomerSubscription |ClubID |EventId |BillingDate| FinalRevenue | Cost
33562784 | 56180001 |5y6m600np1fg| 5/31/2017 | 512 |200
It serves the purpose because each subscription has one cost which is unique BUT it on the other hand, this kind of query will not give me breakdown of dates of billings (I need it for the breakeven calculation)
Table A join B left join on eventId (Group by billingdate
idCustomerSubscription| ClubID |EventId | BillingDate| FinalRevenue |Cost
33562784 | 56180001| 5y6m600np1fg |5/30/2017 |510 |200
33562784 | 56180001| 5y6m600np1fg |5/31/2017 |2 |200
This would give me the breakdown of the dates which i need for breakeven (510 on 30th and 2 on 31st) but it will make the cost duplicated (400 is the cost instead of 200)
I want to find out a SQL magic where I can keep the number of unique subcriptions per row and some way to track the billing dates of each subscriptions in the same query (without grouping it by date because it will make the rows duplicated). Is it possible ?
Perhaps some way where when the eventids are joined and its grouped by date, it doesnt duplicate the cost and count only one cost per eventid?
I hope you will get your desired result with below query. Try to modify your group by operation for mn (alias name) table.
select mn.idCustomerSubscription,mn.ClubID,mn.EventId,mn.BillingDate,mn.FinalRevenue,sq.cost
from tableA Mn left join (select idCustomerSubscription,max(cost) cost, min(billingDate) billingDate from tableA a left join tableB b on a.eventid=b.eventid group by idCustomerSubscription) sq on mn.idCustomerSubscription=sq.idCustomerSubscription and mn.billingDate=sq.billingdate
group by mn.idCustomerSubscription,mn.ClubID,mn.EventId,mn.BillingDate

Postgres LEFT JOIN with WHERE condition

I need to left join two tables with a where condition:
Table time_table
id rid start_date end_date
1 2 2017-07-01 00:00:00 2018-11-01 00:00:00
2 5 2017-01-01 00:00:00 2017-06-01 00:00:00
3 2 2018-07-01 00:00:00 2020-11-01 00:00:00
Table record_table
id name date
1 record1 2017-10-01 00:00:00
2 record2 2017-02-01 00:00:00
3 record3 2017-10-01 00:00:00
I need to get all those records which are present under given date range. In the above example, I need those records that lie under range for rid = 2 only. Hence the output for the above query needs to be:
1 record1 2017-10-01 00:00:00
3 record3 2017-10-01 00:00:00
left join two tables with a where condition
It's typically wrong to use a LEFT [OUTER] JOIN and then filter with a WHERE condition, thereby voiding the special feature of a LEFT JOIN to include all rows from the left table unconditionally. Detailed explanation:
Explain JOIN vs. LEFT JOIN and WHERE condition performance suggestion in more detail
Put conditions supposed to filter all rows into the WHERE clause (rid = 2), but move conditions on record_table to the join clause:
SELECT t.start_date, t.end_date -- adding those
, r.id, r.name, r.date
FROM time_table t
LEFT JOIN record_table r ON r.date >= t.start_date
AND r.date < t.end_date
WHERE t.rid = 2;
As commented, it makes sense to include columns from time_table in the result, but that's my optional addition.
You also need to be clear about lower and upper bounds. The general convention is to include the lower and exclude the upper bound in time (timestamp) ranges. Hence my use of >= and < above.
Related:
SQL query on a time series to calculate the average
Selecting an average of records grouped by 5 minute periods
Performance should be no problem at all with the right indexes.
You need an index (or PK) on time_table(rid) and another on record_table(date).
I'm not exactly sure if this is what you want, but if you are saying you want the dates where the record_table date is between the dates in the time_table, then this would do the job:
select
rt.id, rt.name, rt.date
from
time_table tt
join record_table rt on
rt.date between tt.start_date and tt.end_date
where
tt.rid = 2
That said, this will be horribly inefficient for large datasets. If your data is relatively small (< 10k records in each table, post-filters), then it probably won't matter much, but if you would need to scale this concept, it would warrant knowing more about your data -- for example, do the dates, always round to the first of each month?
Again, from your example, I wasn't sure if this is what you meant by "get all those records which are present under given date range."
SELECT time_tbl.name,record_tbl.date
FROM dbo.time_table AS time_tbl
INNER JOIN record_table AS record_tbl
ON time_tbl.id=record_tbl.id
WHERE(time_tbl.rid=2)

MySQL LEFT JOIN SUM doen not include 0

Guess there are many varianat of this question, however this has a twist.
My primary table contains logged kilometers for certain dates for certain users:
Table km_run:
|entry|mnumber|dato |km | where 'dato' is the specific date. Formats are like:
|1 |3 |2013-01-01|5.7|
For a specific user ('mnumber') I want to calculate the sum in each week of a year. For this purpose I have made a 'dummy-table' just containing the week numbers from 1 to 53:
Table `week_list`:
|week|
|1 |
|2 |
etc..
This query gives the sum, however I cannot find a way to return a zero if there are no entries in 'km_run' for the specific week.
SELECT `week_list`.`week`, WEEKOFYEAR(`km_run`.`dato`), SUM(`km_run`.`km`)
FROM `week_list` LEFT JOIN `km_run` ON WEEKOFYEAR(`dato`) = `week_list`.`week`
WHERE `km_run`.`mnumber` = 3 AND `km_run`.`dato` >= '2013-01-01'
AND `km_run`.`dato` < '2014-01-01'
GROUP BY WEEKOFYEAR(`dato`)
I have tried to do COALESCE( SUM(km),0) and I have also tried to use the IFNULL function around the sum. Despite the left join, not all records from week_list are returned in the sql statement.
Here's the result:
week | WEEKOFYEAR(`km_run`.`dato`) | SUM(`km_run`.`km`)
1 | 1 | 58.4
3 | 3 | 50.7
4 | 4 | 39.2
As you can see, week two is skipped instead of returning a 0
Firstly JOIN works, creating such rows:
week=2 weekofyear=null mnumber=null sum=0 ...
Then, WHERE clause (for example, where mnumber=3) excludes rows with nulls.
You could try something like this:
SELECT week, SUM(km) FROM (
(SELECT km_run.km AS km, WEEKOFYEAR(km_run.dato) AS week
FROM km_run
WHERE mnumber = 3 AND km_run.dato >= '2013-01-01' AND km_run.dato < '2014-01-01')
UNION
(SELECT 0 AS km, week_list.week as week FROM week_list)
) GROUP BY week

MySQL - Count Yearly Totals when some Years have nulls

I have 1 table with similar data:
CustomerID | ProjectID | DateListed | DateCompleted
123456 | 045 | 07-29-2010 | 04-03-2011
123456 | 123 | 10-12-2011 | 11-30-2011
123456 | 157 | 12-12-2011 | 02-10-2012
123456 | 258 | 06-07-2011 | NULL
Basically, a customer contacts us, we get a project on our list, and we mark it completed when we're done with it.
What I'm after is a simple (you'd think, at least) count of all projects, with expected output like below:
YEAR | TotalListed | TotalCompleted
2010 | 1 | 0
2011 | 3 | 2
2012 | 0 | 1
However, my query below - because of the join - isn't showing 2012's count, because there's been no listed project for 2012. However, I can't really reverse the query, as then 2010's count wouldn't show up (since nothing was completed in 2010).
I'm open to any suggestions, or tips like how to do this. I've pondered a temp table, is that the best way to go? I'm open to anything that gets me what I need!
(If the code looks familiar, ya'll helped me get the subquery made! MySQL Subquery with main query data variable)
SELECT YEAR(p1.DateListed) AS YearListed, COUNT(p1.ProjectID) As Listed, PreQuery.Completed
FROM(
SELECT YEAR(DateCompleted) AS YearCompleted, COUNT(ProjectID) AS Completed
FROM projects
WHERE CustomerID = 123456 AND DateListed >= DATE_SUB(Now(), INTERVAL 5 YEAR)
GROUP BY YEAR(DateCompleted)
) PreQuery
RIGHT OUTER JOIN projects p1 ON PreQuery.YearCompleted = YEAR(p1.DateListed)
WHERE CustomerID = 123456 AND DateListed >= DATE_SUB(Now(), INTERVAL 5 YEAR)
GROUP BY YearListed
ORDER BY p1.DateListed
After reviewing your table, query, and expected results - I believe I have found a more-revised query to suit your needs. It is a fairly-full rewrite of your existing query though, but I've tested it with your given data and received the same results you want/expect:
SELECT
years.`year`,
SUM(IF(YEAR(DateListed) = years.`year`, 1, 0)) AS TotalListed,
SUM(IF(YEAR(DateCompleted) = years.`year`, 1, 0)) AS TotalCompleted
FROM
projects
LEFT JOIN (
SELECT DISTINCT `year` FROM (
SELECT YEAR(DateListed) AS `year` FROM projects
UNION SELECT YEAR(DateCompleted) AS `year` FROM projects WHERE DateCompleted IS NOT NULL
) as year_inner
) AS years
ON YEAR(DateListed) = `year`
OR YEAR(DateCompleted) = `year`
WHERE
CustomerID = 123456 AND DateListed >= DATE_SUB(Now(), INTERVAL 5 YEAR)
GROUP BY
years.`year`
ORDER BY
years.`year`
To explain, we should start with the inner query (aliased as year_inner). It selects a full list of years in the DateListed and DateCompleted columns and then selects a DISTINCT list of those to create the years alias sub-query. This sub-query is used to get a full list of "years" that we want data for. Doing it this way, opposed to a sub-query with counts and groupings will allow you to only have to define the WHERE clause on the outermost query (though, if efficiency becomes an issue with thousands and thousands of records, you could always add a WHERE clause to the inner query too; or an index to the date columns).
After we've built our inner queries, we join the projects table on the results with a LEFT JOIN for the DateListed or DateCompleted's YEAR() value - which will allow us to bring back null columns too!
For the field selections, we use the year column from our inner query to assure that we get a full list of years to display. Then, we compare the current row's DateListed & DateCompleted YEAR() value to the current year; if they're equal, add 1 - else add 0. When we GROUP BY year, our SUM() will count all of the 1's for that year for each column and give you the output you want (hopefully, of course =P).