I have a calendar table in which there are all the dates in the future and a workday field:
fld_date / fld_workday
2014-01-01 / 1
2014-01-02 / 1
2014-01-03 / 0
...
I want select a date which are n workday far from another date. I tried two ways, but i failed:
The 5th workday from 2014-11-07:
1.
SELECT n1.fld_date FROM calendar as n1 WHERE n1.fld_workday=1 AND
(select count(*) FROM calendar as n2 WHERE n2.fld_date>='2014-11-07' AND n2.fld_workday=1)=5
It gave back 0 row.
2.
SELECT fld_date FROM calendar WHERE fld_date>='2014-11-07' AND fld_workday=1 LIMIT 1 OFFSET 5
It's ok, but i would like to change the 5 days constant to a field, and it's cannot (it would be inside a bigger select statement):
SELECT fld_date FROM calendar WHERE fld_date>='2014-11-07' AND fld_workday=1 LIMIT 1 OFFSET fld_another_field
Any suggestion?
In the first query, the subquery does not refer to the row in n1.
You need a correlated subquery:
SELECT fld_Date
FROM Calendar AS n1
WHERE fld_WorkDay = 1
AND (SELECT COUNT(*)
FROM Calendar AS n2
WHERE fld_Date BETWEEN '2014-11-07' AND n1.fld_Date
AND fld_WorkDay = 1
) = 5
LIMIT 1
The subquery is extremly inefficient if there is no index on the fld_Date column.
You can avoid executing the subquery for every row in n1 by adding another condition with an estimate of the result date (assuming that there are between about four to five work days per week, and using a few extra days to be sure):
...
WHERE fldDate BETWEEN date('2014-11-07', (5 * 4/7 - 10) || ' days')
AND date('2014-11-07', (5 * 5/7 + 10) || ' days')
AND fldWorkDay = 1
AND (SELECT ...
Related
I want to display the hourly based report for the last 24 hour. I have tried but the problem is that it will display count only where particular hour contains data.
But I want to display count for an hour and if count not found then display 0 over there.
select
datepart(hour, upload_date) as [hour], count(*)
from
tbl_stories
where
upload_date > getdate() - 1
group by
datepart(hour, upload_date)
Output:
hour count
-------------
11 2
16 1
17 1
but I want to get a record in the following way.
hour count
-------------
1 0
2 0
3 5
.
.
.
.
24 1
You can use a value() clause to generate all the hours and then use left join:
select v.hh, count(s.upload_date)
from (values (0), (1), . . . (23)
) v(hh) left join
tbl_stories s
on datepart(hour, s.upload_date) = v.hh and
s.upload_date > getdate() - 1
group by v.hh
order by v.hh;
Note that hours go from 0 to 23.
If you don't want to list out the hours, a convenient generation method is a recursive CTE:
with hours as (
select 1 as hh
union all
select hh + 1
from hours
where hh < 23
)
select h.hh, count(s.upload_date)
from hours h
tbl_stories s
on datepart(hour, s.upload_date) = h.hh and
s.upload_date > getdate() - 1
group by h.hh
order by h.hh;
I have a table that contains two time stamp t1(event open date) and t2(event close date) and a primary key eventid.
If event is open then t2 will be null whenever even gets closed the same row will be get updated with event closure date t2.
For example I want to check how many issues are open on every day bases on opened date (t1) from 01-apr-2016 to 10-apr-2016.
I have to calculate how many events are open for every day based on a selected date range.
Lets say if eventid 1 has got opened on 1st-APR and got closed on 10th-APR and I am calculating the number of opened issues for every day on 11th-APR then it should give me number of open event 1 from 1st-APR to 10th-APR.
Table Structure:-
================================================
EVENTID T1 T2
================================================
1 01-apr-2016 10-apr-2016
2 02-apr-2016 08-apr-2016
3 05-apr-2016 09-apr-2016
Expected Output:-
==============================================================================
DATE TOTAL_OPEN_EVENTS
==============================================================================
01-apr-2016 1
02-apr-2016 2(1 issue open on 1st(not closed on 2nd) and 1 on 2nd)
03-apr-2016 2
04-apr-2016 2
05-apr-2016 3
06-apr-2016 3
07-apr-2016 3
08-apr-2016 2(1 issue got closed on 8th(which was opened on 2nd))
09-apr-2016 2
10-apr-2016 0
How to do this kind of calculation in Oracle database ?
In order to generate the end report, you need a row for each date in your desired range. You could either use a calendar table, if available, or I find using a query on DUAL using CONNECT BY LEVEL < some_number works well to generate rows on the fly. (In this case "some_number" will be the number of days you want to report on.)
From there, you just need to join the individual dates to the date ranges in your event table:
-- create table "events" table
create table event_date_ranges
as
select 1 as event_id, TO_DATE('2016-APR-01', 'YYYY-MM-DD') as start_date, TO_DATE('2016-APR-10', 'YYYY-MON-DD') as end_date from dual
union all
select 2 as event_id, TO_DATE('2016-APR-02', 'YYYY-MM-DD') as start_date, TO_DATE('2016-APR-08', 'YYYY-MON-DD') as end_date from dual
union all
select 3 as event_id, TO_DATE('2016-APR-05', 'YYYY-MM-DD') as start_date, TO_DATE('2016-APR-09', 'YYYY-MON-DD') as end_date from dual
;
with
date_range_qry as
(-- one way to set the start and end dates for your report
select TO_DATE('2016-APR-01', 'YYYY-MM-DD') as report_start_date
, TO_DATE('2016-APR-10', 'YYYY-MM-DD') as report_end_date
from dual
)
, dates_qry
as
(
-- generate a row for all dates between 2016-APR-01 and 2016-APR-10
select report_start_date + ROWNUM - 1 as report_date
from dual
cross join
date_range_qry drq
connect by level <= (drq.report_end_date - drq.report_start_date + 1)
)
select dq.report_date, count(edr.event_id) as total_open_events
from dates_qry dq
left outer join
event_date_ranges edr
on dq.report_date >= edr.start_date
and dq.report_date < edr.end_date
group by dq.report_date
order by dq.report_date
Output:
REPORT_DATE TOTAL_OPEN_EVENTS
2016-APR-01 1
2016-APR-02 2
2016-APR-03 2
2016-APR-04 2
2016-APR-05 3
2016-APR-06 3
2016-APR-07 3
2016-APR-08 2
2016-APR-09 1
2016-APR-10 0
You can try this:
create table events_log
as
select 1 as event_id, TO_DATE('01-04-2016', 'DD/MM/YYYY') as T1, TO_DATE('10-04-2016', 'DD/MM/YYYY') as T2 from dual
union all
select 2 as event_id, TO_DATE('02-04-2016', 'DD/MM/YYYY') as T1, TO_DATE('08-04-2016', 'DD/MM/YYYY') as T2 from dual
union all
select 3 as event_id, TO_DATE('05-04-2016', 'DD/MM/YYYY') as T1, TO_DATE('09-04-2016', 'DD/MM/YYYY') as T2 from dual
;
--------------
select v.REPORT_DATE, count(t.EVENT_ID) as open_event
from events_log t,
(select to_date('01/04/2016', 'DD/MM/YYYY') + ROWNUM - 1 as report_date
from dual
connect by level <= (to_date('11/04/2016', 'DD/MM/YYYY') -
to_date('01/04/2016', 'DD/MM/YYYY') + 1)) v
where t.T1(+) <= v.report_date
and t.T2(+) >= v.report_date
group by v.report_date
order by v.report_date;
Output will be:
report_date open_event
01/04/2016 1
02/04/2016 2
03/04/2016 2
04/04/2016 2
05/04/2016 3
06/04/2016 3
07/04/2016 3
08/04/2016 3
09/04/2016 2
10/04/2016 1
11/04/2016 0
I'm having trouble trying to wrap my head around how to write this query to calculate the occupancy level of a hotel and then list the results by date. Consider the following type of data from a table called reservations:
Arrival Departure Guest Confirmation
08/01/2015 08/05/2015 John 13234
08/01/2015 08/03/2015 Bob 34244
08/02/2015 08/03/2015 Steve 32423
08/02/2015 08/02/2015 Mark 32411
08/02/2015 08/04/2014 Jenny 24422
Output Data would ideally look like:
Date Occupancy
08/01/2015 2
08/02/2015 4
08/03/2015 2
08/04/2015 1
08/02/2015 0
And the query should be able to utilize a date range as a variable. I'm having trouble getting the obviously hardest piece of how to both get the count per night and spitting it out by date.
You can generate a list of dates first. In Oracle you can do this by using connect by. This will make a recursive query. For instance, to get the next 30 days, you can select today and keep connecting until you've got the desired number of days. level indicates the level of recursion.
select trunc(sysdate) + level - 1 as THEDATE
from dual
connect by level <= 30;
On that list, you can query the number of reservations for each day in that period:
select THEDATE,
(select count(*)
from reservations r
where r.Arrival >= THEDATE and
r.Departure < THEDATE) as RESERVATIONCOUNT
from
( select trunc(sysdate) + level - 1 as THEDATE,
from dual
connect by level <= 30)
Instead of getting a fixed number of dates, you can also get another value there, for instance, to get at least 30 days in the future, but further if there are reservations for later..:
select THEDATE,
(select count(*)
from reservations r
where r.Arrival >= THEDATE and
r.Departure < THEDATE) as RESERVATIONCOUNT
from
( select trunc(sysdate) + level - 1 as THEDATE,
from dual
connect by
level <= greatest(30, (select trunc(max(DEPARTURE) - sysdate)
from reservations)))
I have gone through a similar post in Stack overflow...
but my query is :
If my table generates a flag in run time execution,then how can I increase Grp_number(generate run time) every time my flag changes.
my Oracle query:
Select emp_id,
Case when MOD(rownum/3)=1 and rownum>1 then 'Y' else 'N' as flag
from Transaction_table
Desired o/p Data format:
emp_id Flag GRP_number
1 N 1
2 N 1
3 N 1
4 Y 2
5 N 2
6 N 2
7 Y 3
You cannot reference a column in another column in the same select list. You need to use sub query to avoid INVALID IDENTIFIER error.
Do it like -
WITH DATA AS(
SELECT emp_id,
CASE
WHEN MOD(rownum/3)=1
AND rownum >1
THEN 'Y'
ELSE 'N' AS flag
FROM Transaction_table
)
SELECT emp_id, flag, SUM(gap) over (PARTITION BY person
ORDER BY DAY) grp
FROM(
SELECT emp_id, flag,
CASE WHEN flag = lag(flag) over (PARTITION BY person
ORDER BY DAY)
THEN 0
ELSE 1
END gap
FROM DATA)
I need some help to build SQL Query. I have table having data like:
ID Date Name
1 1/1/2009 a
2 1/2/2009 b
3 1/3/2009 c
I need to get result something like...
1 1/1/2009 a
2 1/2/2009 b
3 1/3/2009 c
4 1/4/2009 Null
5 1/5/2009 Null
6 1/6/2009 Null
7 1/7/2009 Null
8 1/8/2009 Null
............................
............................
............................
30 1/30/2009 Null
31 1/31/2009 Null
I want query something like..
Select * from tbl **where month(Date)=1 AND year(Date)=2010**
Above is not completed query.
I need to get all the record of particular month, even if some date missing..
I guess there must be equi Join in the query, I am trying to build this query using Equi join
Thanks
BIG EDIT
Now understand the OPs question.
Use a common table expression and a left join to get this effect.
DECLARE #FirstDay DATETIME;
-- Set start time
SELECT #FirstDay = '2009-01-01';
WITH Days AS
(
SELECT #FirstDay as CalendarDay
UNION ALL
SELECT DATEADD(d, 1, CalendarDay) as CalendarDay
FROM Days
WHERE DATEADD(d, 1, CalendarDay) < DATEADD(m, 1, #FirstDay)
)
SELECT DATEPART(d,d.CalendarDay), **t.date should be (d.CalendarDay)**, t.Name FROM Days d
LEFT JOIN tbl t
ON
d.CalendarDay = t.Date
ORDER BY
d.CalendarDay;
Left this original answer at bottom
You need DATEPART, sir.
SELECT * FROM tbl WHERE DATEPART(m,Date) = 1
If you want to choose month and year, then you can use DATEPART twice or go for a range.
SELECT * FROM tbl WHERE DATEPART(m,Date) = 1 AND DATEPART(yyyy,Date) = 2009
Range :-
SELECT * FROM tbl WHERE Date >= '2009-01-01' AND Date < '2009-02-01'
See this link for more info on DATEPART.
http://msdn.microsoft.com/en-us/library/ms174420.aspx
You can use less or equal to.
Like so:
select * from tbl where date > '2009-01-01' and date < '2009-02-01'
However, it is unclear if you want month 1 from all years?
You can check more examples and functions on "Date and Time Functions" from MSDN
Create a temporary table containing all days of that certain month,
Do left outer join between that table and your data table on tempTable.month = #month.
now you have a big table with all days of the desired month and all the records matching the proper dates + empty records for those dates who have no data.
i hope that's what you want.