I have a table where I store all status changes and the time that it has been made. So, when I search the order number on the table of times I get all the dates of my changes, but what I realy want is the time (hours/minutes) that the order was in each status.
The table of time seems like this
ID_ORDER | Status | Date
1 Waiting 27/09/2017 12:00:00
1 Late 27/09/2017 14:00:00
1 In progress 28/09/2017 08:00:00
1 Validating 30/09/2017 14:00:00
1 Completed 30/09/2017 14:00:00
Thanks!
Use lead():
select t.*,
(lead(date) over (partition by id_order order by date) - date) as time_in_order
from t;
Related
I want to increase the row number of a partition based on a condition. This question refers to the same problem, but in my case, the column I want to condition on is another window function.
I want to identify the session number of each user (id) depending on how long ago was their last recorded action (ts).
My table looks as follows:
id ts
1 2022-08-01 09:00:00 -- user 1, first session
1 2022-08-01 09:10:00
1 2022-08-01 09:12:00
1 2022-08-03 12:00:00 -- user 1, second session
1 2022-08-03 12:03:00
2 2022-08-01 11:04:00 -- user 2, first session
2 2022-08-01 11:07:00
2 2022-08-25 10:30:00 -- user 2, second session
2 2022-08-25 10:35:00
2 2022-08-25 10:36:00
I want to assign each user a session identifier based on the following conditions:
If the user's last action was 30 or more minutes ago (or doesn't exist), then increase (or initialize) the row number.
If the user's last action was less than 30 minutes ago, don't increase the row number.
I want to get the following result:
id ts session_id
1 2022-08-01 09:00:00 1
1 2022-08-01 09:10:00 1
1 2022-08-01 09:12:00 1
1 2022-08-03 12:00:00 2
1 2022-08-03 12:03:00 2
2 2022-08-01 11:04:00 1
2 2022-08-01 11:07:00 1
2 2022-08-25 10:30:00 2
2 2022-08-25 10:35:00 2
2 2022-08-25 10:36:00 2
If I had a separate column with the seconds since their last session, I could simply add 1 to each user's partitioned sum. However, this column is a window function itself. Hence, the following query doesn't work:
select
id
,ts
,extract(
epoch from (
ts - lag(ts, 1) over(partition by id order by ts)
)
) as seconds_since -- Number of seconds since last action (works well)
,sum(
case
when coalesce(
extract(
epoch from (
ts - lag(ts, 1) over (partition by id order by ts)
)
), 1800
) >= 1800 then 1
else 0 end
) over (partition by id order by ts) as session_id -- Window inside window (crashes)
from
t
order by
id
,ts
ERROR: Aggregate window functions with an ORDER BY clause require a frame clause
Use LAG() window function to get the previous ts of each row and create flag column indicating if the difference between the 2 timestamps is greater than 30 minutes.
Then use SUM() window function over that flag:
SELECT
id
,ts
,SUM(flag) OVER (
PARTITION BY id
ORDER BY ts
rows unbounded preceding -- necessary in aws-redshift
) as session_id
FROM (
SELECT
*
,COALESCE((LAG(ts) OVER (PARTITION BY id ORDER BY ts) < ts - INTERVAL '30 minute')::int, 1) flag
FROM
tablename
) t
;
See the demo.
I have the following table.
id user time_stamp
1 Mike 2020-02-13 00:00:00 UTC
2 John 2020-02-13 00:00:00 UTC
3 Levy 2020-02-12 00:00:00 UTC
4 Sam 2020-02-12 00:00:00 UTC
5 Frodo 2020-02-11 00:00:00 UTC
Let's say 2020-02-13 00:00:00 UTC is the last day and I would like to query this table to only display last days results? I want to create a view in Bigquery so that I only and always get the last day's results?
So that in the end I get something like this (For last day which is 2020-02-13 00:00:00 UTC )
id user time_stamp
1 Mike 2020-02-13 00:00:00 UTC
2 John 2020-02-13 00:00:00 UTC
You can use window functions:
select t.* except (seqnum)
from (select t.*,
dense_rank() over (order by time_stamp) as seqnum
from t
) t
where seqnum = 1;
This may not work well on a large amount of data -- because of the way that BQ implements window functions with no partitioning. So, you might find that this works better (especially if the above runs out of resources):
select t.*
from t join
(select max(time_stamp) as max_time_stamp
from t
) tt
on t.time_stamp = max_time_stamp;
Also, if the timestamps actually have date components, then you will want to convert to a date or remove the time component somehow.
I have been trying to separate groups in data being stored on my oracle database for more accurate analysis.
Current Output
Time Location
10:00 A111
11:00 A112
12:00 S111
13:00 S234
17:00 A234
18:00 S747
19:00 A878
Desired Output
Time Location Group Number
10:00 A111 1
11:00 A112 1
12:00 S111 1
13:00 S234 1
17:00 A234 2
18:00 S747 2
19:00 A878 3
I have been trying to use over and partition by to assign the values, however I can only get into to increment all the time not only on a change. Also tried using lag but I struggled to make use of that.
I only need the value in the second column to start from 1 and increment when the first letter of field 1 changes (using substr).
This is my attempt using row_number but I am far off I think. There would be a time column in the output as well not shown above.
select event_time, st_location, Row_Number() over(partition by
SUBSTR(location,1,1) order
by event_time)
as groupnumber from pic
Any help would be really appreciated!
Edit:
Time Location Group Number
10:00 A-10112 1
11:00 A-10421 1
12:00 ST-10621 1
13:00 ST-23412 1
17:00 A-19112 2
18:00 ST-74712 2
19:00 A-87812 3
It is a gap and island problem. Use the following code:
select location,
dense_rank() over (partition by SUBSTR(location,1,1) order by grp)
from
(
select (row_number() over (order by time)) -
(row_number() over (partition by SUBSTR(location,1,1) order by time)) grp,
location,
time
from data
) t
order by time
dbfiddle demo
The main idea is in the subquery which isolates consecutive sequences of items (computation of grp column). The rest is simple once you have the grp column.
select DENSE_RANK() over(partition by SUBSTR("location",1,1) ORDER BY SUBSTR("location",1,2))
as Rownumber,
"location" from Table1;
Demo
http://sqlfiddle.com/#!4/21120/16
I have the following table, I am using SQL Server 2008
BayNo FixDateTime FixType
1 04/05/2015 16:15:00 tyre change
1 12/05/2015 00:15:00 oil change
1 12/05/2015 08:15:00 engine tuning
1 04/05/2016 08:11:00 car tuning
2 13/05/2015 19:30:00 puncture
2 14/05/2015 08:00:00 light repair
2 15/05/2015 10:30:00 super op
2 20/05/2015 12:30:00 wiper change
2 12/05/2016 09:30:00 denting
2 12/05/2016 10:30:00 wiper repair
2 12/06/2016 10:30:00 exhaust repair
4 12/05/2016 05:30:00 stereo unlock
4 17/05/2016 15:05:00 door handle repair
on any given day need do find the highest number of fixes made on a given bay number, and if that calculated number is repeated then it should also appear in the resultset
so would like to see the result set as follows
BayNo FixDateTime noOfFixes
1 12/05/2015 00:15:00 2
2 12/05/2016 09:30:00 2
4 12/05/2016 05:30:00 1
4 17/05/2016 15:05:00 1
I manage to get the counts of each but struggling to get the max and keep the highest calculated repeated value. can someone help please
Use window functions.
Get the count for each day by bayno and also find the min fixdatetime for each day per bayno.
Then use dense_rank to compute the highest ranked row for each bayno based on the number of fixes.
Finally get the highest ranked rows.
select distinct bayno,minfixdatetime,no_of_fixes
from (
select bayno,minfixdatetime,no_of_fixes
,dense_rank() over(partition by bayno order by no_of_fixes desc) rnk
from (
select t.*,
count(*) over(partition by bayno,cast(fixdatetime as date)) no_of_fixes,
min(fixdatetime) over(partition by bayno,cast(fixdatetime as date)) minfixdatetime
from tablename t
) x
) y
where rnk = 1
Sample Demo
You are looking for rank() or dense_rank(). I would right the query like this:
select bayno, thedate, numFixes
from (select bayno, cast(fixdatetime) as date) as thedate,
count(*) as numFixes,
rank() over (partition by cast(fixdatetime as date) order by count(*) desc) as seqnum
from t
group by bayno, cast(fixdatetime as date)
) b
where seqnum = 1;
Note that this returns the date in question. The date does not have a time component.
Is is possible to select a datetime field from a MySQL table and group by the date only?
I'm trying to output a list of events that happen at multiple times, grouped by the date it happened on.
My table/data looks like this: (the timestamp is a datetime field)
1. 2010-03-21 18:00:00 Event1
2. 2010-03-21 18:30:00 Event2
3. 2010-03-30 13:00:00 Event3
4. 2010-03-30 14:00:00 Event4
I want to output something like this:
March 21st
1800 - Event 1
1830 - Event 2
March 30th
1300 - Event 3
1400 - Event 4
Thanks!
select date_format(created_at, "%Y-m-%d") as date from tablename GROUP BY date
OR
SELECT DATE_FORMAT(date_column, '%H%i') as time, event FROM table ORDER BY DATE_FORMAT(date_column, '%Y-%m-%d'), time
SELECT DATE_FORMAT(date_column, '%H%i'), DATE_FORMAT(date_column, '%M %D'), event FROM table ORDER BY date_column
%H%i - 1830
%M%D - March 21st