How to extract time in HH24:MM from varchar in Oracle - sql

I have a column in the following varchar format. I would like to extract the time based on a condition e.g. < 7:00.
Table1
Column: timer(varchar)
23:45
05:00
07:00
22:00
Expected output
test
05:00
07:30
I tried the following:
Select *
FROM Table1
where timer < 7:00
However, the result is not as expected.

Oracle does not have a time date, so presumably the type is a string.
Use string comparisons:
where time < '07:00'
Note that the leading 0 is important!

If this is just time and you want a proper comparison then you can convert them to date and compare them.
Select *
FROM Table1
where to_date(timer,'hh24:mi') < to_date('07:00','hh24:mi');
please note that your expected output contains 07:30 but it is not less than 07:00 so it will not be part of the output if you compare it with less than 07:00.
Cheers!!

Related

Change timestamp without effect date

I am using SSMS and I have a table with date/time stored in a column. What i need to do is change the time but leave the date.
Example: 2020-07-28 00:00:00. I need to change the timestamp 00:00:00 to 23:59:00 without changing the date for the whole column.
CPRDate -- Column Header
2020-07-28 00:00:00
2020-01-01 00:00:00
2017-01-01 00:00:00
You can just add them together -- as datetimes:
select cprdate + convert(datetime, convert(time, '23:59:00'))
This construct is clearly documented and supported by SQL Server:
The plus (+) and minus (-) operators can also be used to run arithmetic operations on datetime and smalldatetime values.
You can use the same construct in an update if you want to change the stored value.
If cprdate is a date, you need to convert it to a datetime for this to work.
You could add subtract one minute and add a day to achieve this, i.e.
update MYTABLE SET CPRDate = DATEADD(day, 1, DATEADD(minute, -1, CPRDATE));
Here's a SQL Fiddle to show it working.

Calculate time difference between two columns of string type in hive without changing the data type string

I am trying to calculate the time difference between two columns of a row which are of string data type. If the time difference between them is less than 2 hours then select the first column of that row else if the time difference is greater than 2 hours then select the second column of that row. It can be done by converting the columns to datetime format, but I want the result to be in string only. How can I do that? The data looks like this:
col1(string type)
2018-07-16 02:23:00
2018-07-26 12:26:00
2018-07-26 15:32:00
col2(string type)
2018-07-16 02:36:00
2018-07-26 14:29:00
2018-07-27 15:38:00
I think you don't need to convert the columns to datetime format, since the data in your case is already ordered (yyyy-MM-dd hh:mm:ss). You just need to take all the digits and take it into one string (yyyyMMddhhmmss) then you can apply your selection which is bigger or smaller than 2 hours (here 20000 since the hour is followed by mmss). By looking at your example (assuming col2 > col1), this query would work:
SELECT case when regexp_replace(col2,'[^0-9]', '')-regexp_replace(col1,'[^0-9]', '') < 20000 then col1 else col2 end as col3 from your_table;
Use unix_timestamp() to convert string timestamp to seconds.
The difference in hours will be:
hive> select (unix_timestamp('2018-07-16 02:23:00')- unix_timestamp('2018-07-16 02:36:00'))/60/60;
OK
-0.21666666666666667
Important update: this method will work correctly only if time zone is configured as UTC. Because for DST timezones for some marginal cases Hive converts time during timestamp operations. Consider this example for PDT time zone:
hive> select hour('2018-03-11 02:00:00');
OK
3
Note the hour is 3, not 2. This is because 2018-03-11 02:00:00 cannot exist in PDT time zone because exactly at 2018-03-11 02:00:00 time is adjusted and becomes 2018-03-11 03:00:00.
The same happens when converting to unix_timestamp. For PDT time zone unix_timestamp('2018-03-11 03:00:00') and unix_timestamp('2018-03-11 02:00:00') will return the same timestamp:
hive> select unix_timestamp('2018-03-11 03:00:00');
OK
1520762400
hive> select unix_timestamp('2018-03-11 02:00:00');
OK
1520762400
And few links for your reference:
https://community.hortonworks.com/questions/82511/change-default-timezone-for-hive.html
http://boristyukin.com/watch-out-for-timezones-with-sqoop-hive-impala-and-spark-2/
Also have a look at this jira please: Hive should carry out timestamp computations in UTC

What does TO_DATE('235959', 'HH24MISS') mean?

I came across a SQL query with below conditional clause
To_Char(CRTE_TMS, 'YYYYmmddHH24MISS') between To_Char (TO_DATE(:endDtTime,'YYYYmmddHH24MISS')-TO_DATE('235959', 'HH24MISS')) and :endDtTime
My high level understanding is that create time stamp should be between some time before end time and end time.
Not sure what does TO_DATE('235959', 'HH24MISS') mean.
If I run the below query on 5th Feb it returns 1st Feb
SELECT TO_DATE('235959', 'HH24MISS') FROM DUAl
Please help me understand what exactly this condition mean.
TO_DATE('235959', 'HH24MISS') creates a DATE value. Note, in Oracle data type DATE always contains date and time part.
If you don't provide any date value then Oracle defaults it to the first day of current months, so TO_DATE('235959', 'HH24MISS') returns "2018-02-01 23:59:59"
I don't think this condition makes sense:
To_Char(CRTE_TMS, 'YYYYmmddHH24MISS')
between To_Char (TO_DATE(:endDtTime,'YYYYmmddHH24MISS')-TO_DATE('235959', 'HH24MISS'))
and :endDtTime
First, you should compare DATE values, not strings.
I assume TO_DATE(:endDtTime,'YYYYmmddHH24MISS')-TO_DATE('235959', 'HH24MISS')) is wrong. I think you mean TO_DATE(:endDtTime,'YYYYmmddHH24MISS') - 1 + (1/24/60/60)
This will subtract 1 day plus 1 Second (1/24/60/60), i.e. subtract 23:59:59.
Another possibility would be TO_DATE(:endDtTime,'YYYYmmddHH24MISS') - INTERVAL '23:59:59' HOUR TO SECOND.
So, your condition could be
WHERE CRTE_TMS between TO_DATE(:endDtTime,'YYYYmmddHH24MISS') - 1 + (1/24/60/60) AND :endDtTime
This could probably be a comment instead of an answer.. Sorry do not have enough reputation.
HH24 is the 24 hour format of the hours.
235959 is 23 hours 59 minutes 59 second.
In a 12 hour format it means 11:59:59 PM.
The thing you are trying to do is converting date format into character and comparing it with other dates by converting them to character format using To_char. I do not suggest that.
The below would give the first of the month
SELECT TO_DATE('235959', 'HH24MISS') FROM DUAl;
I am not able to understand what you are trying to achieve here.
The below syntax gives in the character format which is the difference between two dates. for example 4 days and 10 hours.
To_Char (TO_DATE(:endDtTime,'YYYYmmddHH24MISS')-TO_DATE('235959', 'HH24MISS'))
and then you are trying to do a comparision like date between (4 days and 10 hours) and :endtime. This is incorrect.
You could use the below to convert to date format.
to_date('01012018 23:59:59','MMDDYYYY HH24:MI:SS')
select case when to_date('01012018 23:59:59','MMDDYYYY HH24:MI:SS') between :begindate and :enddate then 1
else null
from dual;

postgresql - Convert string to time

I have column where I saved the transaction time, format is HHMMSS
for example:
140159
013115
235900
then I want to convert those time to HH:MM AM/PM
so results would be:
2:01 PM
1:31 AM
11:59 PM
Here are the queries ive tried, but none of them return the results I want..
SELECT TO_CHAR(TO_TIMESTAMP(TRANSTIME,'hh24:mi:ss AM'),'hh12:mi:ss AM')
FROM PRODUCTSALES order by TRANSTIME desc LIMIT 100
SELECT TO_TIMESTAMP(TRANSTIME, 'HH24:MI')::TIME
time data type is just time - not a format. to get time with wanted format use to_char, eg fro your 140159:
t=# select to_char('140159'::time,'HH:MI AM');
to_char
----------
02:01 PM
(1 row)
Mind I first cast as time and only then format it

Time Difference in Redshift

how to get exact time Difference between two column
eg:
col1 date is 2014-09-21 02:00:00
col2 date is 2014-09-22 01:00:00
output like
result: 23:00:00
I am getting result like
Hours Minutes Seconds
--------------------
3 3 20
1 2 30
using the following query
SELECT start_time,
end_time,
DATE_PART(H,end_time) - DATE_PART(H,start_time) AS Hours,
DATE_PART(M,end_time) - DATE_PART(M,start_time) AS Minutes,
DATE_PART(S,end_time) - DATE_PART(S,start_time) AS Seconds
FROM user_session
but i need like
Difference
-----------
03:03:20
01:02:30
Use DATEDIFF to get the seconds between the two datetimes:
DATEDIFF(second,'2014-09-23 00:00:00.000','2014-09-23 01:23:45.000')
Then use DATEADD to add the seconds to '1900-01-01 00:00:00':
DATEADD(seconds,5025,'1900-01-01 00:00:00')
Then CAST the result to a TIME data type (note that this limits you to 24 hours max):
CAST('1900-01-01 01:23:45' as TIME)
Then LTRIM the date part of the value off the TIME data (as discovered by Benny). Redshift does not allow use of TIME on actual stored data:
LTRIM('1900-01-01 01:23:45','1900-01-01')
Now, do it in a single step:
SELECT LTRIM(DATEADD(seconds,DATEDIFF(second,'2014-09-23 00:00:00','2014-09-23 01:23:45.000'),'1900-01-01 00:00:00'),'1900-01-01');
:)
SELECT LTRIM(DATEADD(seconds,DATEDIFF(second,'2014-09-23 00:00:00','2014-09-23 01:23:45.000'),'1900-01-01 00:00:00'),'1900-01-01');