I have a requirement to take every 3 seconds data within the specific time interval in SQL. I am new to SQL so can anyone help me on the scenario
This is my select query which returns all the values but i need data for every 3 seconds only
SELECT ton_nbr
FROM
icr_file_interface
WHERE
(
reading_dttm BETWEEN
TO_DATE(concat('2016-10-19',to_char(0930)),'yyyy-mm-dd HH24MISS')
AND TO_DATE(concat('2016-10-19',to_char('0945')),'yyyy-mm-dd HH24MISS')
)
AND
(
ton_nbr BETWEEN
(SELECT value FROM text_para WHERE para_cd='ICR_ST_RNG')
AND (SELECT value FROM text_para WHERE para_cd='ICR_ED_RNG')
)
If you only need to subtract 3 seconds from a date, you can use the following:
SQL> select to_char(sysdate, 'yyyy-mm-dd hh24:mi:ss'),
2 to_char(sysdate - 3*1/24/60/60, 'yyyy-mm-dd hh24:mi:ss')
3 from dual;
TO_CHAR(SYSDATE,'YY TO_CHAR(SYSDATE-3*1
------------------- -------------------
2016-10-19 09:38:17 2016-10-19 09:38:14
Given that sysdate -1 means "subtract one day to sysdate", you can derive the number of seconds you need with a bit af arithmetic
This selects you data between last 3 seconds. Hope you got the idea.
select ton_nbr
from icr_file_interface
where reading_dttm between dateadd(ss, -3, getdate()) and getdate() ;
Related
I was curious to see how in Oracle 12c you can take a timestamp datatype and convert the records into EPOCH time to make them a number and then use that number to find any records within that date column that are within 1 minute of each other (assuming the same day if needed, or simply any calculations within 1 minute).
I tried the following but got an ORA-01873: the leading precision of the interval is too small error.
select (sold_date - to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS'))*86400 as epoch_sold_date from test1;
What is SOLD_DATE? For e.g. SYSDATE (function that returns DATE datatype), your code works OK.
SQL> select (sysdate
2 - to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS')
3 ) * 86400 as epoch_sold_date
4 from dual;
EPOCH_SOLD_DATE
---------------
1600807918
SQL>
As SOLD_DATE is a timestamp, but - it appears that fractions of a second aren't or special interest to you, cast it to DATE:
select (cast (systimestamp as date) --> this
- to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS')
) * 86400 as epoch_sold_date
from dual;
Saying that you get the same result for all rows: well, I don't, and you shouldn't either if SOLD_DATE differs.
SQL> with test (sold_date) as
2 (select timestamp '2020-09-22 00:00:00.000000' from dual union all
3 select timestamp '2015-03-18 00:00:00.000000' from dual
4 )
5 select sold_date,
6 (cast (sold_date as date)
7 - to_date('1970-01-01 00:00:00','YYYY-MM-DD HH24:MI:SS')
8 ) * 86400 as epoch_sold_date
9 from test;
SOLD_DATE EPOCH_SOLD_DATE
------------------------------ ---------------
22.09.20 00:00:00,000000000 1600732800
18.03.15 00:00:00,000000000 1426636800
SQL>
One more edit: when you subtract two timestamps, result is interval day to second. If you extract minutes from it, you get what you wanted:
SQL> with test (sold_date) as
2 (select timestamp '2020-09-22 10:15:00.000000' from dual union all
3 select timestamp '2015-03-18 08:05:00.000000' from dual
4 )
5 select sold_date,
6 lead(sold_date) over (order by sold_date) next_sold_date,
7 --
8 lead(sold_date) over (order by sold_date) - sold_date diff,
9 --
10 extract(day from lead(sold_date) over (order by sold_date) - sold_date) diff_mins
11 from test
12 order by sold_date;
SOLD_DATE NEXT_SOLD_DATE DIFF DIFF_MINS
------------------------------ ------------------------------ ------------------------------ ----------
18.03.15 08:05:00,000000000 22.09.20 10:15:00,000000000 +000002015 02:10:00.000000000 2015
22.09.20 10:15:00,000000000
SQL>
In your case, you'd check whether extracted minutes value is larger than 1 (minute).
If you just want to see how many minutes are there between two timestamps, then
cast them to dates
subtract those dates (and you'll get number of days)
multiply it by 24 (as there are 24 hours in a day) and by 60 (as there are 60 minutes in an hour)
Something like this:
SQL> with test (date_1, date_2) as
2 (select timestamp '2020-09-22 10:15:00.000000',
3 timestamp '2020-09-22 08:05:00.000000' from dual
4 )
5 select (cast(date_1 as date) - cast(date_2 as date)) * 24 * 60 diff_minutes
6 from test;
DIFF_MINUTES
------------
130
SQL>
If you are just looking to compare dates and find rows that are within one minute of each other, you do not need to use epoch time. There are several solutions to this problem on this thread.
I have a table abc as:
-- start_time |end_time | total_time_taken
-- 27.05.2020 00:52:48 |27.05.2020 02:08:33 |
I want to set the value of total_time_taken as the difference of end_time-start_time. in the format "HH:MM:SS".I searched the similar topic but didnot find the exact answer.
My expected output is like : 01:44:12 (HH:MM:SS)
So,i tried :
SELECT To_Char(end_time,'HH24:MM:SS'),To_Char(start_time,'HH24:MM:SS'),
To_Char(end_time,'HH24:MM:SS')-To_Char(start_time,'HH24:MM:SS') FROM abc;
The datatypes of start_time,end_time,total_time_taken is DATE.Please help me to find the solution.
If you cast those dates as timestamps, you can easily subtract them and see relatively nice result:
SQL> with test (st, et) as
2 (select to_date('27.05.2020 00:52:48', 'dd.mm.yyyy hh24:mi:ss'),
3 to_date('27.05.2020 02:08:33', 'dd.mm.yyyy hh24:mi:ss')
4 from dual
5 )
6 select cast(et as timestamp) - cast(st as timestamp) diff
7 from test;
DIFF
--------------------------------------------------------------------------
+000000000 01:15:45.000000
SQL>
If you want to format it as you wanted (note that mm format mask is for months; mi is for minutes), then you could do some extracting - again from timestamp (won't work for date):
SQL> with test (st, et) as
2 (select to_date('27.05.2020 00:52:48', 'dd.mm.yyyy hh24:mi:ss'),
3 to_date('27.05.2020 02:08:33', 'dd.mm.yyyy hh24:mi:ss')
4 from dual
5 ),
6 diff as
7 (select cast(et as timestamp) - cast(st as timestamp) diff
8 from test
9 )
10 select extract(hour from diff) ||':'||
11 extract(minute from diff) ||':'||
12 extract(second from diff) diff
13 from diff;
DIFF
-------------------------------------------------------------------------
1:15:45
SQL>
You can further make it pretty (e.g. two digits for hours, using LPAD function). Or, you can even write your own function which will actually work on difference of DATE datatype values, do some calculations (using trunc function, subtractions, whatnot), but the above looks pretty elegant if compared to a home-made function.
The answer by Littlefoot is perfectly fine. This answer is just to show there is more than one way to get the result.
First, we can subtract one date from another and get the difference in days, then convert that difference to an interval.
with test (st, et) as
(select to_date('27.05.2020 00:52:48', 'dd.mm.yyyy hh24:mi:ss'),
to_date('27.05.2020 02:08:33', 'dd.mm.yyyy hh24:mi:ss')
from dual
)
select numtodsinterval(et-st, 'day') diff
from test;
Then, since we can't control interval formatting directly, we can add DIFF to an arbitrary date and then use built-in date formatting.
with test (st, et) as
(select to_date('27.05.2020 00:52:48', 'dd.mm.yyyy hh24:mi:ss'),
to_date('27.05.2020 02:08:33', 'dd.mm.yyyy hh24:mi:ss')
from dual
)
select to_char(date '1-1-1' + numtodsinterval(et-st, 'day'), 'hh24:mi:ss') diff
from test;
DIFF
--------
01:15:45
I want to migrate a table which contains some columns with dates. The issue is my dates are often in dd/mm/yyyyy HH24:MM:YYYY format. But sometimes it appears that the format is only dd/mm/yyyy, or blank.
I guess that's why I'm getting ORA-01830 when I'm trying to migrate the datas.
I tried
CASE
WHEN TO_DATE(MYDATE,'DD/MM/YYYY')
then TO_DATE(MYDATE,'DD/MM/YYYY 00:00:00')
END AS MYDATE
But I'm not sure if it is possible to test the date format (and ofcourse it's not working).
Thank you
TO_DATE cannot test date format, but you can do it. If Lalit's answer would not be enough, try something like
select
case when my_date like '__/__/__' then to_date(my_date, 'dd/mm/yy')
when my_date like '__-__-__' then to_date(my_date, 'dd-mm-yy')
...
end
So you have the data type issue. DATE is stored as string literal. As you have mentioned that the date model has the DD/MM/YYYY part same, just that the time portion is either missing for some rows or the entire value is NULL.
For example, let's say your table have the values like -
SQL> WITH dates AS(
2 SELECT 1 num, '29/12/2014 16:38:57' dt FROM dual UNION ALL
3 SELECT 2, '29/12/2014' FROM dual UNION ALL
4 SELECT 3, NULL FROM dual
5 )
6 SELECT num, dt
7 FROM dates
8 /
NUM DT
---------- -------------------
1 29/12/2014 16:38:57
2 29/12/2014
3
SQL>
TO_DATE with proper format model should do the trick.
Let's stick to a format model first.
SQL> alter session set nls_date_format='dd/mm/yyyy hh24:mi:ss';
Session altered.
Now, let's use TO_DATE to explicitly convert the string literal to date.
SQL> WITH dates AS(
2 SELECT 1 num, '29/12/2014 16:38:57' dt FROM dual UNION ALL
3 SELECT 2, '29/12/2014' FROM dual UNION ALL
4 SELECT 3, NULL FROM dual
5 )
6 SELECT num, to_date(dt, 'dd/mm/yyyy hh24:mi:ss') dt
7 FROM dates
8 /
NUM DT
---------- -------------------
1 29/12/2014 16:38:57
2 29/12/2014 00:00:00
3
SQL>
i am using timestamp for a field to store date and time, however when i fetch the rows from the table i get loads of zeros in the timestamp field.
SQL> select * from booking_session;
BK_ID|BK_DATE
----------|-------------------------
1|18-MAR-12 10.00.00.000000
2|18-MAR-12 10.25.00.000000
3|18-MAR-12 10.30.00.000000
4|18-MAR-12 10.35.00.000000
5|18-MAR-12 10.40.00.000000
The following is the insert statement
INSERT INTO BOOKING_SESSION VALUES (1,TO_TIMESTAMP('18/03/2012 10:00',
'DD/MM/YYYY HH24:MI')
Can someone please tell me how can the bk_date format be stored like 18-MAR-12 10.00 or at least have AM or PM next to it.
Thanks in advance.
You can declare BK_DATE column as timestamp(precision) where precision is a number of decimal digits to store fraction of a second. So you might have declared BK_DATE timestamp(0). If you do not need track time down to a fraction of a second use date data type to store dates. In any case time part (hh:mi:ss) will be there and if you insert data as you did, specifying only hour and minutes, then seconds will be fill in with zeros. You can use to_char function and appropriate date format mask to get rid of those trailing zeros at display time:
-- sample of data
SQL> with t1(BK_ID, BK_DATE) as(
2 select 1, to_timestamp('18-MAR-12 10.00.00.000000', 'DD-MON-RR HH:MI:SSxFF6') from dual union all
3 select 2, to_timestamp('18-MAR-12 10.25.00.000000', 'DD-MON-RR HH:MI:SSxFF6') from dual union all
4 select 3, to_timestamp('18-MAR-12 10.30.00.000000', 'DD-MON-RR HH:MI:SSxFF6') from dual union all
5 select 4, to_timestamp('18-MAR-12 10.35.00.000000', 'DD-MON-RR HH:MI:SSxFF6') from dual union all
6 select 5, to_timestamp('18-MAR-12 10.40.00.000000', 'DD-MON-RR HH:MI:SSxFF6') from dual
7 )
8 select bk_id
9 , to_char(bk_date, 'DD-MON-RR HH:MI') bk_date
10 from t1
11 ;
BK_ID BK_DATE
---------- ------------------------
1 18-MAR-12 10:00
2 18-MAR-12 10:25
3 18-MAR-12 10:30
4 18-MAR-12 10:35
5 18-MAR-12 10:40
Try the following query:
select * from booking_session where trunc(bk_date) = to_date('18-03-2012', 'dd-mm-yyyy');
The question I need to answer is this "What is the maximum number of page requests we have ever received in a 60 minute period?"
I have a table that looks similar to this:
date_page_requested date;
page varchar(80);
I'm looking for the MAX count of rows in any 60 minute timeslice.
I thought analytic functions might get me there but so far I'm drawing a blank.
I would love a pointer in the right direction.
You have some options in the answer that will work, here is one that uses Oracle's "Windowing Functions with Logical Offset" feature instead of joins or correlated subqueries.
First the test table:
Wrote file afiedt.buf
1 create table t pctfree 0 nologging as
2 select date '2011-09-15' + level / (24 * 4) as date_page_requested
3 from dual
4* connect by level <= (24 * 4)
SQL> /
Table created.
SQL> insert into t values (to_date('2011-09-15 11:11:11', 'YYYY-MM-DD HH24:Mi:SS'));
1 row created.
SQL> commit;
Commit complete.
T now contains a row every quarter hour for a day with one additional row at 11:11:11 AM. The query preceeds in three steps. Step 1 is to, for every row, get the number of rows that come within the next hour after the time of the row:
1 with x as (select date_page_requested
2 , count(*) over (order by date_page_requested
3 range between current row
4 and interval '1' hour following) as hour_count
5 from t)
Then assign the ordering by hour_count:
6 , y as (select date_page_requested
7 , hour_count
8 , row_number() over (order by hour_count desc, date_page_requested asc) as rn
9 from x)
And finally select the earliest row that has the greatest number of following rows.
10 select to_char(date_page_requested, 'YYYY-MM-DD HH24:Mi:SS')
11 , hour_count
12 from y
13* where rn = 1
If multiple 60 minute windows tie in hour count, the above will only give you the first window.
This should give you what you need, the first row returned should have
the hour with the highest number of pages.
select number_of_pages
,hour_requested
from (select to_char(date_page_requested,'dd/mm/yyyy hh') hour_requested
,count(*) number_of_pages
from pages
group by to_char(date_page_requested,'dd/mm/yyyy hh')) p
order by number_of_pages
How about something like this?
SELECT TOP 1
ranges.date_start,
COUNT(data.page) AS Tally
FROM (SELECT DISTINCT
date_page_requested AS date_start,
DATEADD(HOUR,1,date_page_requested) AS date_end
FROM #Table) ranges
JOIN #Table data
ON data.date_page_requested >= ranges.date_start
AND data.date_page_requested < ranges.date_end
GROUP BY ranges.date_start
ORDER BY Tally DESC
For PostgreSQL, I'd first probably write something like this for a "window" aligned on the minute. You don't need OLAP windowing functions for this.
select w.ts,
date_trunc('minute', w.ts) as hour_start,
date_trunc('minute', w.ts) + interval '1' hour as hour_end,
(select count(*)
from weblog
where ts between date_trunc('minute', w.ts) and
(date_trunc('minute', w.ts) + interval '1' hour) ) as num_pages
from weblog w
group by ts, hour_start, hour_end
order by num_pages desc
Oracle also has a trunc() function, but I'm not sure of the format. I'll either look it up in a minute, or leave to see a friend's burlesque show.
WITH ranges AS
( SELECT
date_page_requested AS StartDate,
date_page_requested + (1/24) AS EndDate,
ROWNUMBER() OVER(ORDER BY date_page_requested) AS RowNo
FROM
#Table
)
SELECT
a.StartDate AS StartDate,
MAX(b.RowNo) - a.RowNo + 1 AS Tally
FROM
ranges a
JOIN
ranges b
ON a.StartDate <= b.StartDate
AND b.StartDate < a.EndDate
GROUP BY a.StartDate
, a.RowNo
ORDER BY Tally DESC
or:
WITH ranges AS
( SELECT
date_page_requested AS StartDate,
date_page_requested + (1/24) AS EndDate,
ROWNUMBER() OVER(ORDER BY date_page_requested) AS RowNo
FROM
#Table
)
SELECT
a.StartDate AS StartDate,
( SELECT MIN(b.RowNo) - a.RowNo
FROM ranges b
WHERE b.StartDate > a.EndDate
) AS Tally
FROM
ranges a
ORDER BY Tally DESC