I've been thinking about how to compose this SQL query for a while now, but after thinking about it for a few hours I thought I'd ask the SO community to see if they have any ideas.
Here is a mock up of the relevant portion of the tables:
contracts
id
date
ar (yes/no)
term
payments
contract_id
payment_date
The object of the query is to determine, per month, how many payments we expect, vs how many payments we received.
conditions for expecting a payment
Expected payments begin on contracts.term months after contracts.date, if contracts.ar is "yes". Payments continue to be expected until the month after the first missed payment.
There is one other complication to this: payments might be late, but they need to show up as if they were paid on the date expected.
The data is all there, but I've been having trouble wrapping my head around the SQL query. I am not an SQL guru - I merely have a decent amount of experience handling simpler queries. I'd like to avoid filtering the results in code, if possible - but without your help that may be what I have to do.
Expected Output
Month Expected Payments Received Payments
January 500 450
February 498 478
March 234 211
April 987 789
...
SQL Fiddle
I've created an SQL Fiddle: http://sqlfiddle.com/#!2/a2c3f/2
Without writing up the query, I can give you the general idea:
In the contracts table, cast date + term in months, and group the result set by months where ar = 'YES'. This gives you the expected payments.
With the second table, cast payment_date in months and group by months for the number of received payments.
You can then join these two sub-results on month to get both pieces of information in one result set.
Related
I am trying to pull a report from a data set , the conditions are as follow:
Customer A,B and C produced 100, 150 and 200 tickets respectively in a year.
A's period from 1/1/2022 till 3/30/2022
B's period from 1/10/2022 till 6/20/2022
C's period from 6/10/2022 till 9/5/2022
I want to pull how many cases each customer produced while they are in the incubation period. Such that the report will not include any cases outside the customers incubation period.
The start date and end date in available in a table.
Hopefully I was able to explain this, thanks for your help.
I started a HR management project and I want to count days between 2 dates without counting the holidays and weekends. So the HR can count employee's day off
Here's the case, I want to count between 2018-02-14 and 2018-02-20 where there is an office holiday on 2018-02-16. The result should be 3 days.
I have already created a table called tbl_holiday where I put all weekends and holidays in one year there
I found this post, and I tried it on my MariaDB
Here's my query:
SELECT 5 * (DATEDIFF('2018-02-20', '2018-02-14') DIV 7) +
MID('0123444401233334012222340111123400012345001234550', 7 *
WEEKDAY('2018-02-14') + WEEKDAY('2018-02-20') + 1, 1) -
(SELECT COUNT(dates) FROM tbl_holiday WHERE dates NOT IN (SELECT dates FROM tbl_holiday)) as Days
The query works but the result is 4 days, not 3 days. It means the query only exclude the weekends but not the holiday
What is wrong with my query? Am I missing something? Thank you for helping me
#RichardDoe, from the question comments.
In a reasonable implementation of a date table, you create a list of all days (covering a sufficient range to cope with any query you may run against it - 15 years each way from today is probably a useful minimum), and alongside each day you store a variety of derived attributes.
I wrote a Q&A recently with basic tools that would get you started in SQL Server: https://stackoverflow.com/a/48611348/9129668
Unfortunately I don't have a MySQL environment or intimate familiarity with it to allow me to write or adapt queries off the top of my head (as I'm doing here), but I hope this will illustrate the structure of a solution for you in SQL Server syntax.
In terms of the answer I link to (which generates a date table on the fly) and extending it by adding in your holiday table (and making some inferences about how you've defined your holiday table), and noting that a working day is any day Mon-Fri that isn't a holiday, you'd write a query like so to get the number of working days between any two dates:
WITH
dynamic_date_table AS
(
SELECT *
FROM generate_series_datetime2('2000-01-01','2030-12-31',1)
CROSS APPLY datetime2_params_fxn(datetime2_value)
)
,date_table_ext1 AS
(
SELECT
ddt.*
,IIF(hol.dates IS NOT NULL, 1, 0) AS is_company_holiday
FROM
dynamic_date_table AS ddt
LEFT JOIN
tbl_holiday AS hol
ON (hol.dates = ddt.datetime2_value)
)
,date_table_ext2 AS
(
SELECT
*
,IIF(is_weekend = 1 OR is_company_holiday = 1, 0, 1) AS is_company_work_day
FROM date_table_ext1
)
SELECT
COUNT(datetime2_value)
FROM
date_table_ext2
WHERE
(datetime2_value BETWEEN '2018-02-14' AND '2018-02-20')
AND
(is_company_work_day = 1)
Obviously, the idea for a well-factored solution is that these intermediate calculations (being general in nature to the entire company) get rolled into the date_params_fxn, so that any query run against the database gains access to the pre-defined list of company workdays. Queries that are run against it then start to resemble plain English (rather than the approach you linked to and adapted in your question, which is ingenious but far from clear).
If you want top performance (which will be relevant if you are hitting these calculations heavily) then you define appropriate parameters, save the lot into a stored date table, and index that table appropriately. This way, your query would become as simple as the final part of the query here, but referencing the stored date table instead of the with-block.
The sequentially-numbered workdays I referred to in my comment on your question, are another step again for the efficiency and indexability of certain types of queries against a date table, but I won't complicate this answer any further for now. If any further clarification is required, please feel free to ask.
I found the answer for this problem
It turns out, I just need to use a simple arithmetic operator for this problem
SELECT (SELECT DATEDIFF('2018-02-20', '2018-02-14')) - (SELECT COUNT(id) FROM tbl_holiday WHERE dates BETWEEN '2018-02-14' AND '2018-02-20');
I am developing a php/mysql database.
I have a table called ‘actions’ which (amongst others) contains fields hrs, mins, actiondate, invoiceid and staffid.
For any particular actiondate there could be any number of actions carried out by various staff who would enter their time as hrs and mins.
What I need to do is produce a table which for each date and for a specific member of staff and invoice, adds up all of the hrs and mins for each date as a decimal, rounds it up to the nearest quarter and displays that result. I also need to be able to add up all of those results and display that total.
For example, if on March 1st, person with staffid=23 had carried out 4 actions for invoiced 121 lasting, 1h2m, 23m, 10m and 20m the total for that day would be 62+23+10+20 = 115m = 115/60 = 1.92 which would be rounded up to 2.00.
I can get each day’s total (maybe not very elegantly) and display it against the date using the code below
SELECT actions.`actiondate`,
(FORMAT((((CEIL((((60*SUM(hrs))+SUM(mins))/60)*4))/4)),2)) AS dayfeeqtr
FROM actions
WHERE staff.staffid=’23’
AND invoiceid=‘121’
GROUP BY actions.`actiondate`
However, what I can’t work out, is how can I add up all of these rounded up results for that invoice and that member of staff.
Can anyone help please?
If I understand correctly, you can use a subquery:
SELECT sum(dayfeeqtr)
FROM (SELECT a.`actiondate`,
FORMAT((((CEIL((((60*SUM(hrs))+SUM(mins))/60)*4))/4)), 2) AS dayfeeqtr
FROM actions a
WHERE s.staffid = '23' AND invoiceid = '121'
GROUP BY a.`actiondate`
) a;
I do note that your query is not correct -- for instance, there is a reference to staff, which is not in a from clause. However, you say that this is working, so I assume the errors are a transcription problem.
I'm having issues getting the desired results from my database. The join_service_date and dropped_service_date columns have dates. The rejects have an r in the column if it is rejected.
I want to be able to count the agents sales, rejects, dropped sales and how many of those sales have dropped our service within 0-30 days, 31-60 days or 61-90 days. I got the results I needed from doing several small queries, but I would like to learn or know how to gather the information in a just 1 or as little as possible queries.
Also how would I specify this for a specific month like march or april.
select agentid,
count(join_service_date),
count(dropped_service_date),
count(rejects),
datediff(day, join_service_date, dropped_service_date)
from dbtable
group by agentid
In rails 3 (also with meta_where gem if you feel like using it in your query), I got a really tricky query that I have been banging my head for:
Suppose I have two models, customers and purchases, customer have many purchases. Let's define customers with at least 2 purchases as "repeat_customer". I need to find the total number of repeat_customers by each day for the past 3 months, something like:
Date TotalRepeatCustomerCount
1/1/11 10 (10 repeat customers by the end of 1/1/11)
1/2/11 15 (5 more customer gained "repeat" status on this date)
1/3/11 16 (1 more customer gained "repeat" status on this date)
...
3/30/11 150
3/31/11 160
Basically I need to group customer count based on the date of creation of their second purchase, since that is when they "gain repeat status".
Certainly this can be achieved in ruby, something like:
Customer.includes(:purchases).all.select{|x| x.purchases.count >= 2 }.group_by{|x| x.purchases.second.created_at.to_date }.map{|date, customers| [date, customers.count]}
However, the above code will fire query on the same lines of Customer.all and Purchase.all, then do a bunch of calculation in ruby. I would much prefer doing selection, grouping and calculations in mysql, since it is not only much faster, it also reduces the bandwith from the database. In large databases, the code above is basically useless.
I have been trying for a while to conjure up the query in rails/active_record, but have no luck even with the nice meta_where gem. If I have to, I will accept a solution in pure mysql query as well.
Edited: I would cache it (or add a "repeat" field to customers), though only for this simplified problem. The criteria for repeat customer can change by the client at any point (2 purchases, 3 purchases, 4 purchases etc), so unfortunately I do have to calculate it on the spot.
SELECT p_date, COUNT(customers.id) FROM
(
SELECT p_date - INTERVAL 1 day p_date, customers.id
FROM
customers NATURAL JOIN purchases
JOIN (SELECT DISTINCT date(purchase_date) p_date FROM purchases) p_dates
WHERE purchases.purchase_date < p_date
GROUP BY p_date, customers.id
HAVING COUNT(purchases.id) >= 2
) a
GROUP BY p_date
I didn't test this in the slightest, so I hope it works. Also, I hope I understood what you are trying to accomplish.
But please note that you should not do this, it'll be too slow. Since the data never changes once the day is passed, just cache it for each day.