We are working with sqlite3 and have encountered one problem.
We have a database for library with several tables, in particular - items table and loans table. When we insert a new item into the loans table, we have to save the Start date and Due date of the loan. The starting date is select Date('now') and the Due date should be calculated as the Start date + exact number of days taken from the items table (= loanduration).
We try to do it with following query:
update loans set Sdate=(SELECT date('now')) where CID=NEW.CID and IID=NEW.IID;
update loans set Ddate= select date(NEW.Sdate, '+' || (select loanduration from items where items.IID=NEW.IID) where CID=NEW.CID and IID=NEW.IID day|| 'day');
However, it doesnt work and we cant find the proper solution.
Can anybody help, please?
According to the documentation, the modifier must be +NNN days:
> SELECT date('now', '+3day');
> SELECT date('now', '+3 day');
2014-03-12
Related
This may be a simple fix but Im somehow drawing a blank. I have this code below, and I want the results that I got from it to be added into their own column in an existing table. How would i go about doing this.
Select full_name, SUM(total) as sum_sales
FROM loyalty
where invoiceyear = 2013
GROUP BY full_name
order by sum_sales DESC;
This leaves me with one column with the name of employee and the second with their sales from that year.
How can i just take these results and add them into a column in addition to the table
Is it as simple as...
Alter table loyalty
Add column "2013 sales"
and then add in some sort of condition?
Any help would be greatly appreciated!
If i got your question right, you need to first alter the table allowing the new field to be null (you can change it later on) then you could use an insert clause to store the value permanently.
Dear StackOverflow Community,
as a New to DB2 ,i have a a query
may be its a very basic question for you, please share your knowledge.
i have a start date and End Date.
I need a list of each and every date in between.
Its ok with me ,if it creates a temp table no issue.
Thanks in Advance
You can generate the dates between start and end dates by using Recursive CTE expression. Try below code
with cte(your_columns,startdate,enddate)
as (select your_columns,startdate,enddate,startdate
as derDate
from yourTable
union all
select your_columns,startdate,enddate,derDate+1
from cte where
derDate<=endDate)
select * from cte
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?
I have a data table and a calendar table. The date table only contains the fields MonthName and FiscalYearName. My calendar table has each day for each year. How can I write the JOIN to make sure I am not getting duplicated data due to the inability to JOIN on a date? Right now am I just linking on those two fields and I am getting duplicate data.
Could you elaborate on the exact issue?
If month and year are the only fields, why exactly do you need to join on Calendar? To get rid of duplicates, the easiest solution might be to use a 'DISTINCT'.
SELECT DISTINCT dat.year, dat.month, *
FROM date dat
JOIN calendar cal
ON dat.year = cal.year
AND dat.month = cal.month
Edit;
Extra query to just show the MonthNum;
This query uses a common table expression which gets the distinct month names and their number only once, then joins the date table on this cte.
WITH cteCalendar AS
(
SELECT DISTINCT MonthName, MonthNum FROM calendar
)
SELECT cte.MonthNum, dat.*
FROM date dat
JOIN cteCalendar cte
AS dat.MonthName = cte.MonthName
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.