Need to split out whole and partial hours from a time period (postgresql) - postgresql

I have a table of data that data that contains a date, time-in, and time-out pulled from a postgresql db table. Currently the table shows the time a person checked in, and out over a period of hours. I need to use postgresql to split out the hours between time-in and time-out such that I capture each full hour (eg. 10am-11am) and each fraction (eg. 4.15pm to 5pm) of the hour during which that person was checked in. So if a person checked in at 9.30am, took a 1 hour lunch break at 12, and checked out at 4.30pm, my current table would show two rows for that member i.e. one row for the time before lunch break, and the time after the lunch break. I want to show each hour (whole or partial) on each row, with 1 representing that 1 whole hour, and the minute portion to capture the partial hour worked.
Below are the before and after images. Any help is appreciated.
Shows that I want to convert from
Shows that I want to convert to
Thanks


try this.
CAST(time_out - time_in AS TIME)

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Repeat each date specific number of times

I have gotten so much help form this forum from times to times, but this is the first time I am posting a question.
What I need is:
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In Column A we have the dates
01/09/2017 (x96 times)
02/09/2017 (x96 times)
...
...
...
30/09/2017 (x96 times)
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So, I need a macro, to check if each date of the month has 96 rows in column A and if not then add the missing rows... It happens some dates to have 70 rows, so in that case I need the macro to insert another 26 rows of the same date...
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PostgreSQL - Have one serial type column but reset every day (unique combination with other date type column)

i need to have this table that will have a serial type column in my PostgreSQL database that will reset every day and will be unique combination with other date type column.
For example today i insert 2 rows
SerialId, Date
1, '08.12.2016'
2, '08.12.2016'
But tomorrow the next insert should be with SerialId = 1 and tomorrows date
1, '09.12.2016' ...
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Thanks in advance.

I would just let the sequence keep running, but if you really want to reset it, you could define a cron job that runs at midnight and issues
ALTER SEQUENCE ... RESET;
If the application is really busy around midnight, you have a race condition there, because there is no guarantee that the sequence will be reset precisely at midnight, but if there is not much traffic at this time you might get away with it.

After midnight times in postgresql

I have data from a text file I'm reading into a postgres 9.1 table, and the data looks like this:
451,22:30:00,22:30:00,San Jose,1
451,22:35:00,22:35:00,Santa Clara,2
451,22:40:00,22:40:00,Lawrence,3
451,22:44:00,22:44:00,Sunnyvale,4
451,22:49:00,22:49:00,Mountain View,5
451,22:53:00,22:53:00,San Antonio,6
451,22:57:00,22:57:00,California Ave,7
451,23:01:00,23:01:00,Palo Alto,8
451,23:04:00,23:04:00,Menlo Park,9
451,23:07:00,23:07:00,Atherton,10
451,23:11:00,23:11:00,Redwood City,11
451,23:15:00,23:15:00,San Carlos,12
451,23:18:00,23:18:00,Belmont,13
451,23:21:00,23:21:00,Hillsdale,14
451,23:24:00,23:24:00,Hayward Park,15
451,23:27:00,23:27:00,San Mateo,16
451,23:30:00,23:30:00,Burlingame,17
451,23:33:00,23:33:00,Broadway,18
451,23:38:00,23:38:00,Millbrae,19
451,23:42:00,23:42:00,San Bruno,20
451,23:47:00,23:47:00,So. San Francisco,21
451,23:53:00,23:53:00,Bayshore,22
451,23:58:00,23:58:00,22nd Street,23
451,24:06:00,24:06:00,San Francisco,24
It is from a timetable for a commuter rail line, Caltrain. I'm trying to query stations, to get train arrival and departure times. I did this several months ago in MySql, and I got
select * from trains as a, trains as b where a.trip_id=b.trip_id and a.st
op_id='San Antonio' and b.stop_id='San Carlos' and a.arrival_time < b.arrival_ti
me;
So far so good, pretty straightforward. However, when I tried copying the data into a postgres database, I got an error for the various columns that had times after midnight, either 24 or 25:00:00 something. However, if I change them to be 00:00:00 and 01:00:00 something, won't that mess with the query? A time after midnight will appear to be before the starting time? MySql apparently didn't have a problem with those times, and I'm not sure what to do. I'm thinking I should use the last column, or maybe convert the times to something that doesn't take into account PM/AM?

You should try using the interval type for the time columns. Those will keep track of the number of hours, minutes, and seconds instead of trying to record a time of day.
See the PostgreSQL documentation on dates and times.
An interval can have a time component greater than 24 hours, unlike the time datatype that is confined to 00:00 <= x <= 23:59.