I have difficulties formulating my issue.
I have a view which brings these results. There's a need to add a column to the view, which will pair up round-trip flights with identical number.
Flt_No From_Airport To_Airport Dep_Date RequiredResult
124 |LCA |CDG |10/19/14 5:00 1
125 |CDG |LCA |10/19/14 10:00 1
197 |LCA |BCN |10/4/12 5:00 2
198 |BCN |LCA |10/4/12 11:00 2
501 |LCA |HER |15/8/12 12:05 3
502 |HER |LCA |15/8/12 15:15 3
I.e. flight 124 is going from Larnaca to CDG, and flight 125 is going back from CDG to Larnaca - they both have to have the same identifier.
Round-trip flights will always have following flight numbers.
I have a bunch of conditions which I won't write now.
Omitting hours is not an option, they're important.
I was thinking dense_rank() but I don't know how to create one identifier for 2 flights with different numbers, please help.
If your data is similar to the sample data posted, then the following query should give the required result:
SELECT *,
DENSE_RANK() OVER (ORDER BY CASE
WHEN From_Airport < To_Airport THEN From_Airport
ELSE To_Airport
END)
FROM mytable
Join conditions are not limited to simple equality. Assuming {Flight No, Departure, Destination} is unique on any one day, then a self join should do it:
select whatever
from flights outbound
inner join flights inbound on outbound.flt_no+1 = inbound.flt_no
and cast(outbound.dep_date, date)
= cast(inbound.dep_date, date)
and outbound.From_Airport = inbound.To_Airport
and outbound.To_Airpott = inbound.From_Ariport
Related
I'm learning some basic SQL skills and I was toying around with some data to see what I can do, however, I'm a bit stuck on how to proceed with my current problem.
I have a table that looks like this:
RouteID
SegmentID
Order
BeginTime
EndTime
CarID
1
45
1
10:00:30
10:01:00
1
1
46
2
10:01:00
10:01:30
1
1
47
3
10:01:30
10:02:00
1
2
50
1
10:05:00
10:05:30
1
2
49
2
10:06:00
10:06:30
1
3
900
1
20:01:00
20:01:30
2
As you can see, we have a bunch of cars and the routes they have driven. A route is simply a sequence of traveled roadsegments. Furthermore, we have the timestamps of entering the segments and leaving the segments.
The goal
What I want to do is to create an easy origin-destination analysis. I'm given a list of segments that belong to location A and similarly, I'm given a list of segments belonging to location B.
My solution
Alright, this is easy. I have made a new table that for each route lists the first and last segment. Using this table, it is then super easy to get the answer.
The problem
The routes themselves are not generated as they should be. In the above table for example, you'll see that car 1 has two routes. The first route end at 10:02:00 whereas the second route begins at 10:05:00. As the this time difference is less that 5 minutes apart, I'd very much like to consider this as 'one route'. I'm not necessarily interested in generating a new table where we glue all routes of the same car together provided that they lie within 5 minutes of each other (although, I'd be very interested in the type of queries one would have to write to accomplish this).
For now, I'd be very happy to get a clue/answer on how to somehow glue these routes together and to make a table where the origin and destination of each route is listed and routes of the same car with at most 5 minutes in between are considered as one route.
I thank you in advance. Although I had some close attempts, a proper solution seems beyond my current (very basic) SQL-skills.
You can compare ordered rows to flag a new route start for a car. And next get a virtual route number within a car. For example
select routeID, SegmentID, [Order], BeginTime, EndTime, CarID,
-- virtual route nbr within a car
sum(newRouteFlag) over(partition by CarID order by BeginTime) rtNmbr
from (
select routeID, SegmentID, [Order], BeginTime, EndTime, CarID,
case when lag(routeID) over(partition by CarID order by BeginTime) = routeID
or dateadd(minute, 5, lag(BeginTime) over(partition by CarID order by BeginTime)) >= BeginTime then 0 else 1 end newRouteFlag
from tbl
) t
I'm running a SELECT query to get data across multiple tables in the same server instance. However I've just noticed that the rows pulled on some data get duplicated because the main table I'm pulling from has a few different values in one of the columns. Here's the query:
SELECT DISTINCT BIF030.C_ACCOUNT AS ACCOUNTNUMBER,
BIF003.C_ACCOUNTTYPE AS ACCOUNTTYPECODE,
CON013.C_DESCRIPTION AS ACCOUNTTYPE,
BIF003.C_DIVISION AS ZONE_DIVISONCODE,
CON028.C_DESCRIPTION AS ZONE_DIVISION,
BIF030.C_METER as METERNUMBER,
BIF005.C_METERCUSTOM1 AS REGISTERNUMBER,
CONVERT(DECIMAL(20,2), BIF030.N_CONSUMP) AS CONSUMPTION,
CON007.C_DESCRIPTION AS UNITS,
BIF030.T_READDATE AS READINGDATE,
MONTH(BIF030.T_READDATE) AS READINGMONTH,
DAY(BIF030.T_READDATE) AS READINGDAY,
YEAR(BIF030.T_READDATE) AS READINGYEAR,
BIF030.I_DAYS AS READINGDAYSCOUNT
FROM ADVANCED.BIF030
LEFT JOIN ADVANCED.CON007 ON CON007.C_UNITS=BIF030.C_UNITS
LEFT JOIN ADVANCED.BIF005 ON BIF005.C_METER=BIF030.C_METER
LEFT JOIN ADVANCED.BIF003 ON BIF003.C_ACCOUNT=BIF030.C_ACCOUNT
LEFT JOIN ADVANCED.CON013 ON CON013.C_ACCOUNTTYPE=BIF003.C_ACCOUNTTYPE
LEFT JOIN ADVANCED.CON028 ON CON028.C_DIVISION=BIF003.C_DIVISION
WHERE T_READDATE > '01-01-2014'
ORDER BY ACCOUNTNUMBER, READINGDATE ASC
I know SELECT DISTINCT is frowned upon, but I get even more rows without it. Here's a sample of what the data looks like when pulled:
ACCOUNTNUMBER
ACCOUNTTYPECODE
ACCOUNTTYPE
ZONE_DIVISIONCODE
ZONE_DIVISION
METERNUMBER
REGISTERNUMBER
CONSUMPTION
UNITS
READINGDATE
READINGMONTH
READINGDAY
READINGYEAR
READINGDAYSCOUNT
1234567
SP
ACCOUNT TYPE 1
00
00-NO ZONE
123456789
987654321
3.00
Thousands of Gallons
2014-01-16 00:00:00.00
1
16
2014
30
1234567
MF
ACCOUNT TYPE 2
02
02-GRAVITY
123456789
987654321
3.00
Thousands of Gallons
2014-01-16 00:00:00.00
1
16
2014
30
1234567
SR
ACCOUNT TYPE 3
02
02-GRAVITY
123456789
987654321
3.00
Thousands of Gallons
2014-01-16 00:00:00.00
1
16
2014
30
I also know the column that is messing this up is the "AccountTypeCode" because other accounts that don't have multiple codes associated with the "AccountNumber" only show 1 set of rows. So this one specifically (and probably others) is tripling the amount of rows pulled when it should only pull one for each "ReadingDate".
Also if anyone knows a good way to optimize the query I'd be happy to learn. I know just enough SQL to be dangerous, but not enough to figure this out. Thanks.
Ok. So good news and I want to add this in case it helps anyone else in the future. I found out that since the ACCOUNTTYPECODE and ZONE_DIVISIONCODE were coming from the table BIF003 I needed to add more in the WHERE statement. This is what fixed it for me:
AND BIF030.C_CUSTOMER = BIF003.C_CUSTOMER
Because the C_CUSTOMER column was different (it's a column in the BIF003 and BIF030 tables) which lead to the separate ACCOUNTTYPECODE results I need to check it in the WHERE statement.
Thanks everyone for kick starting my brain on this one.
I have a very big transaction table on DB2 v11, and I need to query a subset of it as efficiently as possible. All I need is the total count of the set (not known in advance, it's based on criteria, lets say 1 day) and the ID of the first record, and the ID of the last record.
The old code was fetching the entire table, then just using the 1st record ID, and the last record ID, and size, and not making use of the rest. Now this code is timing out. It's a complex query of several joins.
IS there a way to just fetch the size of the set, 1st record, last record all in one select query ?
I've read that reordering the list in order to fetch the 1st record(so fetch with Desc, then change to Asc) is not efficient.
sample table 1 TRANSACTION_RECORDS:
tdID TIMESTAMP name
-------------------------------
123 2020-03-31 john
234 2020-03-31 dan
456 2020-03-01 Eve
675 2020-04-01 joy
sample table 2 TRANSACTION_TYPE:
invoiceId tdID account
------------------------------
897 123 abc
898 123 def
877 234 mnc
899 456 opp
Sample query
select Min(tr.transaction_id), Max(tr.transaction_id)
from TRANSACTION_RECORDS TR
join TRANSACTION_TYPE TT
on TR.tdID=tt.tdID
WHERE Date(TR.TIMESTAMP) = '2020-03-31'
group by tr.tdID
order by TR.tdID ASC
This results in multiple columns, (but it requires the group by)
123,123
234,234
456,456
What I want is:
123,456
As I mentioned in the comments, for this query you don't need Group BY and neither Order by, just do:
select Min(tr.transaction_id), Max(tr.transaction_id)
from TRANSACTION_RECORDS TR
join TRANSACTION_TYPE TT
on TR.tdID=tt.tdID
WHERE Date(TR.TIMESTAMP) = '2020-03-31'
It should work as expected
i tried to ready a lot of date comparisons that i found here on stackoverflow and spread into the internet but i wasn't able to find the solution.
I have the following table (Trips):
VehicleID DriverID xID CheckIn CheckOut DateHour
462 257 7 1 0 16/12/2017 20:40:00
462 257 7 0 1 19/12/2017 10:05:00
5032 3746 11 1 0 02/10/2017 07:00:00
5032 3746 11 0 1 06/10/2017 17:00:00
When my company receives a traffic ticket, i want to compare the date from the ticket with the hole block of dates from the table "Trips", each block starts with CheckIn = 1 and finishes with CheckOut = 1, so this way i will know which driver was responsable for the ticket through the DriverID.
For example: the traffic ticket date and time are: 17/12/2017 08:00:00 and the Vehicle is the one with id = 462, i'll insert this date and time in a field in our system to consult automaticaly which driver was driving that car at that moment, we won´t use the ticket table yet. Looking at my example, i know it should return DriverID = 257, but theres a lot of trips with the same vehicle and diferent drivers.....The major problem is how can i compare the Date and Hour from the Ticket with the range of dates from the trips, since i have to consider 1 trip = 2 lines in the table
Unfortunately i can't change the way this table was created, cause we need this 2 lines, CheckIn and CheckOut, separately.
Any thoughts or directions?
Thank you for your attention
select t1.VehicleID
,t1.DriverID
,t1.xID
,t1.DateHour as Checkin
,t2.DateHour as Checkout
from trips as t1 join trips as t2 --self join trips to get both start and end in a single row
on t1.VehicleID = t2.VehicleID -- add all columns
and t1.DriverID = t2.DriverID -- which define
and t1.xID = t2.xID -- a unique trip
and t1.Checkin = 1 -- start
and t2.Checkout = 1 -- end
join tickets -- now join tickets
on tickets.trafficDateHour between t1.DateHour and t2.DateHour
I didn't make sample tables, this will not run as is, but something like this should do it for you:
SELECT *
FROM tickets, trips
WHERE
trips.datehour in (
SELECT trips.datehour
FROM tickets, trips
WHERE
tickets.ticket_date < trips.datehour AND
trips.checkin = 0
) AND
tickets.ticket_date > trips.datehour AND
trips.checkin = 1
If you are running this for a specific date as described in the comment above, it will work. If you are trying to run it for a set of ticket dates all at once, you'll require recursion. Recursion is a different beast depending on your flavor of SQL.
I have a person's flight history and want to find their most frequent route. All flights are stored as a single row in a table, even return trips where a->b will be in one row and b->a will be in another.
I need to identify where two legs equate to a route; for example:
This person has flown 16 times in total
New York to Paris 2 times (Flight key: JFKCDG)
Paris to New York 2 times (Flight Key: CDGJFK)
New York to London 3 times (Flight Key: JFKLHR)
Currently I don't know a way to group the first two above as a 'Route' and therefore any query I write considers JFKLHR to be the most frequent route (6 times between NY and London) even though I can see from the data that this person has flown between NY and Paris a total of 10 times
Sample Table:
User ID¦Flight Key
-------------------
1 ¦JFKCDG
1 ¦JFKCDG
1 ¦CDGJFK
1 ¦CDGJFK
1 ¦JFKLHR
1 ¦JFKLHR
1 ¦JFKLHR
Expected Output
User ID¦Flight Key¦Count
------------------------
1 ¦JFKCDGJFK ¦4
Building on the clever idea in the answer by #fancyPants. You can use string functions to compare each leg of a route and patch together a full return trip.
I believe this query should work. The first part of the common table expression turns those flights that are round trips into three parts (src-dst-src) and the second part returns those that are one way (as src-dst).
with flights_cte as (
select
USERID,
case when left(flightkey,3) > right(flightkey,3)
then concat(flightkey, left(flightkey,3))
else concat(right(flightkey,3), flightkey)
end as flightkey,
count(*) count
from flights f
where exists (
select 1 from flights where right(f.flightkey,3) = left(flightKey,3)
)
group by
userid,
case
when left(flightkey,3) > right(flightkey,3)
then concat(flightkey, left(flightkey,3))
else concat(right(flightkey,3), flightkey)
end
union all
select userid, FlightKey, count(*)
from flights f
where not exists (
select 1 from flights where right(f.flightkey,3) = left(flightKey,3)
)
group by UserID, FlightKey
)
select flights_cte.userid, flights_cte.flightkey, flights_cte.count
from flights_cte
join (select userid, max(count) _max_count from flights_cte group by userid) _max
on flights_cte.UserID=_max.UserID and flights_cte.count = _max_count
A sample SQL Fiddle gives this output:
| USERID | FLIGHTKEY | COUNT |
|--------|-----------|-------|
| 1 | JFKCDGJFK | 4 |
Assuming routes are not a single row, otherwise you wouldn't be asking.. (although I would guess that the whole route is in some other table, maybe reservation-related)
Guessing the first step is to group this data by person and flights that compose a 'route'. I have an article called T-SQL: Identify bad dates in a time series where the time series can be modified to detect gaps between legs of over a day (guess) to differentiate routes. Second step would be to convert legs into route, i.e. JFK-CDG and CDG-JFK to single value JFK-CDG-JFK.
Then it would be a single query, counting the above single value route, and ORDER BY that count.
Good luck.