I have a calendar table called CalendarInformation that gives me a list of dates from 2015 to 2025. This table has a column called BusinessDay that shows what dates are weekends or holidays. I have another table called OpenProblemtimeDiffTable with a column called number for my problem number and a date for when the problem was opened called ProblemNew and another date for the current column called Now. What I want to do is for each problem number grab its date ranges and find the dates between and then sum them up to give me the number of business days. Then I want to insert these values in another table with the problem number associated with the business day.
Thanks in advance and I hope I was clear.
TRUNCATE TABLE ProblemsMoreThan7BusinessDays
DECLARE #date AS date
DECLARE #businessday AS INT
DECLARE #Startdate as DATE, #EndDate as DATE
DECLARE CONTACT_CURSOR CURSOR FOR
SELECT date, businessday
FROM CalendarInformation
OPEN contact_cursor
FETCH NEXT FROM Contact_cursor INTO #date, #businessday
WHILE (##FETCH_STATUS=0)
BEGIN
SELECT #enddate= now FROM OpenProblemtimeDiffTable
SELECT #Startdate= problemnew FROM OpenProblemtimeDiffTable
SET #Date=#Startdate
PRINT #enddate
PRINT #startdate
SELECT #businessday= SUM (businessday) FROM CalendarInformation WHERE date > #startdate AND date <= #Enddate
INSERT INTO ProblemsMoreThan7BusinessDays (businessdays, number)
SELECT #businessday, number
FROM OpenProblemtimeDiffTable
FETCH NEXT FROM CONTACT_CURSOR INTO #date, #businessday
END
CLOSE CONTACT_CURSOR
DEALLOCATE CONTACT_CURSOR
I tried this code using a cursor and I'm close, but I cannot get the date ranges to change for each row.
So if I have a problemnumber with date ranges between 02-07-2018 and 05-20-2019, I would want in my new table the sum of business days from the calendar along with the problem number. So my output would be column number PROB0421 businessdays (with the correct sum). Then the next problem PRB0422 with date ranges of 11-6-18 to 5-20-19. So my output would be PROB0422 with the correct sum of business days.
Rather than doing this in with a cursor, you should approach this in a set based manner. That you already have a calendar table makes this a lot easier. The basic approach is to select from your data table and join into your calendar table to return all the rows in the calendar table that sit within your date range. From here you can then aggregate as you require.
This would look something like the below, though apply it to your situation and adjust as required:
select p.ProblemNow
,p.Now
,sum(c.BusinessDay) as BusinessDays
from dbo.Problems as p
join dbo.calendar as c
on c.CalendarDate between p.ProblemNow and p.Now
and c.BusinessDay = 1
group by p.ProblemNow
,p.Now
I think you can do this without a cursor. Should only require a single insert..select statement.
I assume your "businessday" column is just a bit or flag-type field that is 1 if the date is a business day and 0 if not? If so, this should work (or something close to it if I'm not understanding your environment properly).:
insert ProblemsMoreThan7BusinessDays
(
businessdays
, number
)
select
number
, sum( businessday ) -- or count(*)
from OpenProblemtimeDiffTable op
inner join CalendarInformation ci on op.problem_new >= ci.[date]
and op.[now] <= ci.[date]
and ci.businessday = 1
group by
problem_number
I usually try to avoid the use of cursors and working with data in a procedural manner, especially if I can handle the task as above. Dont think of the data as 1000's of individual rows, but think of the data as only two sets of data. How do they relate?
Related
I have a table in Postgres 14.2
Table name is test
There are 3 columns: date, high, and five_day_mavg (date is PK if it matters)
I have a select statement which properly calculates a 5 day moving average based on the data in high.
select date,
avg(high) over (order by date rows between 4 preceding and current row) as mavg_calc
from test
It products output as such:
I have 2 goals:
First to store the output of the query in five_day_mavg.
Second to store this in such a way that when I a new row with data
in high, it automatically calculates that value
The closest I got was:
update test set five_day_mavg = a.mav_calc
from (
select date,
avg(high) over (order by date rows between 4 preceding and current row) as mav_calc
from test
) a;
but all that does is sets the value of every row in five_day_mavg to entire average of high
Thanks to #a_horse_with_no_name
I played around with the WHERE clause
update test l set five_day_mavg = b.five_day_mavg from (select date, avg(high) over (order by date rows between 4 preceding and current row) as five_day_mavg from test )b where l.date = b.date;
a couple of things. I defined each table. The original table I aliased as l, the temporary table created by doing a windows function (the select statement in parenthesis) I aliased as b and I joined with the WHERE clause on date which is the index/primary key.
Also, I was using 'a' as the letter for alias, and I think that may have contributed to the issue.
Either way, solved now.
I have problem select data between two dates if the only start_date is available.
The example I want to see is what discount_nr was active between 2020-07-01 and 2020-07-15 or only one day 2020-07-14. I tried different solutions, date range, generate series, and so on, but was still not able to get it to work.
Table only have start dates, no end dates
Example:
discount_nr, start_date
1, 2020-06-30
2, 2020-07-03
3, 2020-07-10
4, 2020-07-15
You can get the end dates by looking at the start date of the next row. This is done with lead. lead(start_date) over(order by start_date asc) will get you the start_date of the next row. If we take 1 day from that we'll get the inclusive end date.
Rather than separate start/end columns, a single daterange column is easier to work with. You can use that as a CTE or create a view.
create view discount_durations as
select
id,
daterange(
start_date,
lead(start_date) over(order by start_date asc)
) as duration
from discounts
Now querying it is easy using range operators. #> to check if the range contains a date.
select *
from discount_durations
where duration #> '2020-07-14'::date
And use && to see if they have any overlap.
select *
from discount_durations
where duration && daterange('2020-07-01', '2020-07-15');
Demonstration
I have a table with a row for each sale of a product. These rows include a date. I want to know the number of products sold for each distinct day in a range (user specifies the begin and end dates.) There is a distinct row for each sale, so on days where several products were sold, several rows with this date exist. I want to count the number of these rows, with the same date. How might this be done efficiently in postgresql?
Example
2015-01-02: 0
2015-01-03: 7
2015-01-04: 2
Assuming the date column is stored as a datetime, something like this should get you in the right direction:
SELECT date_trunc('day', TIMESTAMP sales.date) as day, COUNT(*)
FROM sales
WHERE day >= start and <= end
GROUP BY day;
where start and end are filled in by the user.
More documentation for postgres's date features found here:
http://www.postgresql.org/docs/9.4/static/functions-datetime.html
If they are not datetime, you can use the to_date function with the appropriate format string to convert to datetime and the use the solution above:
SELECT date_trunc('day', to_date('2015-01-02', 'YYYY-MM-DD'));
http://www.postgresql.org/docs/9.4/static/functions-formatting.html
I have a table for Inventory Dollars by Vendor by Month. I want to be able to update the dollar amounts for the current month on a daily basis, but I don't want to lose the previous month's data. Here is the basic query I have:
DELETE Inventory_Dollars
FROM Inventory_Summary
WHERE MonthNum = '4'
SELECT
SUM(Cost*OnHand) AS Inventory_Dollars
FROM Inventory
The Inventory table will always hold the current data. How can I just Insert Into Inventory_Summary the data from the Select statement?
Just preface your query with an INSERT:
INSERT INTO Inventory_Summary
(Inventory_Dollars)
SELECT SUM(Cost * OnHand) AS Inventory_Dollars
FROM Inventory
If you've already inserted the inventory_dollars amount for the current month, you can then update the value every day with something like this:
UPDATE Inventory_Summary
SET Inventory_Dollars = (
SELECT (Cost * OnHand)
FROM Inventory
)
WHERE MonthNum = DATEPART(m, GETDATE()) AND Year = DATEPART(year, GETDATE())
The DATEPART can be used to fill in the number of the month for the current date, GETDATE(). Then you won't be updating the inventory_dollars values for past months.
Edit: Also added a year to the where clause, so you don't update months from past years.
Edit 2: If you use a subquery in the SET, make sure only one result can come back.
I need to sum values that are + 2 months or within a quarter period (related date table)
is there a way to use dense rank to partition those periods (custom periods)?
select
FiscalMonth
,Value
from table
The sql will have to do the following:
Join the value table and the period table
Include the period in the select list and sum the value, grouping by the period
i.e
select b.period, sum(a.value)
from table a
inner join period b on a.FiscalMonth between b.StartMonth and b.EndMonth
group by b.period
Note: The join condition will have to be modified based on what data you actually have in the period table.
Hope this helps
Well, If you need value from an X interval, by month you could use something like:
SELECT *
FROM yourTable
MONTH(some_date) = MONTH(CURRENT_DATE - INTERVAL 1 MONTH) //Could be X interval!
This is an example (which show the results of the previous month, from the actual one). Just trying to write that it is possible to massage the query in functions on intervals.
Of course, you could use the SUMcommand for the adding.