Find out if current time is between two times

Question

I have two time columns stored in a Postgresql database: open_time and close_time. I'm trying to find out if the current time, ignoring the date, is between the two times, ignoring the dates.

This code compares the dates as well as the time:

current_time = Time.now
if current_time.between?(store.open_time, store.close_time)
  puts "IN BETWEEN"      
end

It doesn't work, for example, when current_time # => 2018-06-06 23:59:49 -0600 and open_time # => 2000-01-01 22:59:00 UTC.

How do I get it to not include the dates, and just compare the times?

That doesn't make sense. Time is a more precise notion than date. You cannot have a particular time without the notion of which date it is. — sawa, Jun 07 '18 at 06:14
@sawa eh? Postgres [perfectly allows](https://www.postgresql.org/docs/9.1/static/datatype-datetime.html) storing times without a date and the fact that ruby does not provide a handy wrapper for it does not mean “time is more precise.” `DateTime` is. — Aleksei Matiushkin, Jun 07 '18 at 06:19
[Comparing times only, without dates?](https://stackoverflow.com/q/14329198/477037) is a similar question, although not Postgres specific. — Stefan, Jun 07 '18 at 07:54
@Stefan, a comment at the link you gave suggests that the earlier question is in fact Postgres-related, but it would be a shame to regard this question a dup because I do not believe any of the earlier answers are correct. — Cary Swoveland, Jun 07 '18 at 18:56
I really appreciate all the answers! I ended up taking ideas from all the answers, so I'm not really sure which of them to mark. — NathanB, Jun 07 '18 at 21:36

Cary Swoveland · Answer 1 · 2018-06-07T08:00:18.893

require 'time'

TIME_FMT = "%H%M%S"

def store_open_now?(open_time, close_time)
  nt = Time.now.strftime(TIME_FMT)
  ot = open_time.strftime(TIME_FMT)
  ct = close_time.strftime(TIME_FMT)
  ot <= ct ? (nt >= ot && nt <= ct) : (nt >= ot || nt <= ct)
end

As I write, the time is now about 32 minutes past midnight.

Time.now.strftime(TIME_FMT)
  #=> "003252"

Suppose

open_time  = DateTime.parse("09:00")
  #=> #<DateTime: 2018-06-07T09:00:00+00:00 ((2458277j,32400s,0n),
  #               +0s,2299161j)>
close_time = DateTime.parse("17:00")
  #=> #<DateTime: 2018-06-07T17:00:00+00:00 ((2458277j,61200s,0n),
  #               +0s,2299161j)>

Then

open_time.strftime(TIME_FMT)
  #=> "090000"
close_time.strftime(TIME_FMT)
  #=> "170000"
store_open_now?(open_time, close_time)
  #=> false

Now suppose the open time is the same, but the close time is later.

close_time = DateTime.parse("01:00")
  #=> #<DateTime: 2018-06-07T01:00:00+00:00 ((2458277j,3600s,0n),
  #               +0s,2299161j)>

Then

close_time.strftime(TIME_FMT)
  #=> "010000"
store_open_now?(open_time, close_time)
  #=> true

sawa · Accepted Answer · 2018-06-07T06:36:38.027

4

Perhaps you want something like this:

current_time = Time.now
open_time = store.open_time
close_time = store.close_time
current_time -= current_time.beginning_of_day
open_time -= open_time.beginning_of_day
close_time -= close_time.beginning_of_day
if current_time.between?(open_time, close_time)
  puts "IN BETWEEN"      
end

or

current_time = Time.now
open_time = store.open_time
close_time = store.close_time
current_time = [current_time.hour, current_time.min, current_time.sec]
open_time = [open_time.hour, open_time.min, open_time.sec]
close_time = [close_time.hour, close_time.min, close_time.sec]
if open_time <=> current_time == -1 and current_time <=> close_time == -1
  puts "IN BETWEEN"      
end

edited Jun 07 '18 at 06:36

answered Jun 07 '18 at 06:22

sawa

165,429
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`Array` does not declare `between?` you need to use smth like `open_time..close_time === current_time`. – Aleksei Matiushkin Jun 07 '18 at 06:25
@mudasobwa You are right. I was starting to feel something wrong about my answer. Thanks. – sawa Jun 07 '18 at 06:26
`Array` implements `<=>` but does *not* include `Comparable`!? – Stefan Jun 07 '18 at 07:41
@Stefan Yes. It looks like `<=>` is defined, but `<` is not. – sawa Jun 07 '18 at 07:48
1

Apparently tokland requested this feature, but [Matz rejected it](https://bugs.ruby-lang.org/issues/5574). What a pity. – Stefan Jun 07 '18 at 07:51
1

Consider: what if the store is a bar? – Cary Swoveland Jun 07 '18 at 07:54
@CarySwoveland Not sure what you mean. Can you expand on that? – sawa Jun 07 '18 at 08:04
The calculation is different if the "store" opens before, but closes after midnight, e.g `18:00` until `03:00` – Stefan Jun 07 '18 at 08:07
I see. But the OP has not asked that kind of question. If that is indeed what the OP wants, then the OP is asking the wrong question. – sawa Jun 07 '18 at 08:10
The OP hasn't mentioned anything about opening hours. They only have a table column named `open_time`. – sawa Jun 07 '18 at 08:15
@sawa has hours some how been removed from the concept of time now? If so then what is `open_time` to you? – engineersmnky Jun 07 '18 at 13:17

Martin · Answer 3 · 2018-09-03T08:50:33.570

You could CAST() your datetime to time by using,

cast(tbl_store.open_time as time) as SomeVariable

cast(tbl_store.close_time as time) as SomeOtherVariable

That would give you the time only instead of the full datetime value that you had to begin with, which is what you wanted.

You can then use the same logic with your curtime() between to the get value that you were looking for.

Example:

SELECT
  CAST(tbl_store.open_time as TIME) as open_time,
  CAST(tbl_store.close_time as TIME) as close_time,
  CURTIME() BETWEEN (cast(tbl_store.open_time as TIME)) AND (cast(tbl_store.close_time as TIME)) as time_between
FROM
  tbl_store

Working SQL Fiddle

You can change the schema build in the fiddle to test the datetime values you desire.

Note that if you ever have a logic that will include midnight time, you will have to make a CASE WHEN logic against that, else it will fail and return 0, whereas it should return 1.

I wish I could upvote this twice. Let the database do database stuff. — Jordan Running, Jun 07 '18 at 16:10

lunohodov · Answer 4 · 2018-06-07T07:23:20.997

0

You can take advantage of ranges and how numeric strings are compared

r = Range.new('09:00', '18:00')

r.include?('08:59') # => false
r.include?('09:01') # => true
r.include?('18:01') # => false

Then we could use

open_hours_range = Range.new(open_time.strftime('%R'), close_time.strftime('%R'))
shop_open? = open_hours_range.include?(Time.now.strftime('%R'))

edited Jun 07 '18 at 07:23

answered Jun 07 '18 at 07:15

lunohodov

5,179
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Find out if current time is between two times

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