How to get weekly records on Rails? - ruby-on-rails

I have Payment model with data and amount attributes. Now I need to get all the records for the current week on the page. I want to use some kind of pagination, e.g.: On the first page I get all records for the current week, on the second page - records from the previous week etc.
And on every page I need to get total amount for this week and average amount per day.
So, I have two questions:
How to get all the records for particular week on the page?
How to count amount for this week?
Now everything I've done was array with weeks and amounts
def self.count_by_week
raw_result = group_by_week_and_state.count
# {['2014-12-01-2014-12-07', 'foo'] => 100, ['2014-12-01-2014-12-07', 'bar'] => 100, '...' => '...'}
raw_result.each_with_object({}) do |(k, v), result|
result[k[0]] ||= {}
result[k[0]][k[1]] = v
end
end
def self.group_by_week_and_state
group("#{weekday_query(0)} || \'-\' || #{weekday_query(6)}").group('amount')
end
# build sql part for day offset of week (0 => mon, 6 => sun)
def self.weekday_query(offset)
"to_char(cast(date_trunc(\'week\', created_at) as date) + #{offset}, \'YYYY-MM-DD\')"
end

You could use the groupdate gem to accomplish this.
https://github.com/ankane/groupdate
Once you have successfully grouped your records, it's just too simple to get the sum for each groups.

Related

Allocate daily sales to date created

Im trying to gather all sales made within a week and put each sale in day made. If Moday was two sales, then Monday => {...}, {...} etc
"Monday" would be ruby's date format.
In my db I have 5 sale objects: Two sales on Monday and two on Tuesday.
Controller:
def daily_customer_sale(created)
date_and_id = Sale.where('created_at >= ?', created).pluck(:created_at, :id)
date_and_id.each do |obj|
yield(obj.first, obj.last)
end
end
def daily_sales(created=nil)
sales_by_date = Hash.new(0)
daily_customer_sale(created) do |date, id|
s_date = date.to_date
sales_by_date[s_date] = Sale.find(id) # Seems to return only one object per day
end
return sales_by_date
end
For views:
daily_sales(1.week.ago.to_datetime)
What I get in two dates (correct) in which each data has only one object when it should be two or more per date. Is there something wrong?
You don't need complex logic to do it. Here is a cleaner way
Sale.where('created_at >= ?', created_at).group_by{ |sale| sale.created_at.to_date}
It will return All the sales grouped by day.
key will be date object and for each day there will be sale array containing all of the sales for that day.
If you need string based key you can format it as you like as per below
Sale.where('created_at >= ?', created_at).group_by{ |sale| sale.created_at.to_date.to_s } #default date format
Sale.where('created_at >= ?', created_at).group_by{ |sale| sale.created_at.to_date.strftime("%d/%m/%Y") } #23/09/2016
You can have a look at Group by method

How do I find the sum of donations per month for 24 months?

Having pulled donations from the past two years, I'm trying to derive the sum of those donations per month (a total of 24 sums), storing the keys (each month) and the values (the sum of donations for each month) in an array of hashes.
Here's what I've got so far:
#donations = Gift.between(Date.today - 2.years, Date.today, :field => gift_date)
#donations.each do |donation|
#logic here that puts gift_amount into the right month (of the 24 months)
# and adds it to the previous balance for that month, ending up with 24 keys
# and sum values.
end
How can I do this in Ruby/Rails?
Continuing where #mbratch left off:
donations = Gift.where(:date => (Date.today - 2.years)..Date.today)
Hash[donations.group_by { |d| [d.date.year, d.date.month] }
.map do |year_month, donations|
[year_month, donations.map(&:amount).reduce(:+)]
end]
donation_hash = Hash.new(0)
Gift.where(:gift_date => (Date.today - 2.years)..Date.today).each do |donation|
donation_hash[[donation.gift_date.month, donation.gift_date.year]] += donation.amount
end
This will create a hash with keys of [month, year] and value of total amount donated for that month/year. There are probably a few other suitable ways to create a key which meets the need of your application.

Ruby on Rails 3 Check In/Check Out ranges by hour

I'm using Ruby on Rails 3 and I have a "visit" model which stores a check_in and check_out datetime and I need to search through visits in a general date range and count the number of "visitors present" grouped by all hours of the day.
...i.e. I need something like:
8:00am - 8:59am : 12 visitors
9:00am - 9:59am : 5 visitors
10:00am - 10:59am : 4 visitors
...given a table of visits with a check in and check out time stored.
The idea is to take check-in and check-out times for "visits" and then determine how many visitors (assuming each visit logs one visitor, which it does by policy) were visiting during any given hour of the day in order to find out peak visiting times.
I've tried setting up queries like:
eight_am_visits = Visit.where("EXTRACT(HOUR_MINUTE FROM check_in) <= 859").where("EXTRACT(HOUR_MINUTE FROM check_out) >= 800")
...and haven't quite hit on it because Rails stores dates in such an odd fashion (in UTC, which it will convert on database query) and it doesn't seem to be doing that conversion when I use something like EXTRACT in SQL...
...any idea how I can do this?
Looks like you're not actually interested in the Visit objects at all. If you just want a simple summary then push AR out of the way and let the database do the work:
# In visit.rb
def self.check_in_summary(date)
connection.select_rows(%Q{
select extract(hour from check_in), count(*)
from visits
where cast(check_in as date) = '#{date.iso8601}'
group by extract(hour from check_in)
}).inject([ ]) do |a, r|
a << { :hour => r[0].to_i, :n => r[1].to_i }
end
end
Then a = Visit.check_in_summary(Date.today - 1) will give you the summary for yesterday without doing any extra work. That demo implementation will, of course, have holes in the array for hours without any checkins but that is easy to resolve (if desired):
def self.check_in_summary(date)
connection.select_rows(%Q{
select extract(hour from check_in), count(*)
from visits
where cast(check_in as date) = '#{date.iso8601}'
group by extract(hour from check_in)
}).each_with_object([0]*24) do |r, a| # Don't forget the arg order change!
a[r[0].to_i] = r[1].to_i
end
end
That version returns an array with 24 elements (one for each zero-based hour) whose values are the number of checkins within that hour.
Don't be afraid to drop down to SQL when it is convenient, AREL is just one tool and you should have more than one tool in your toolbox. Also, don't be afraid to add extra data mangling and summarizing methods to your models, your models should have an interface that allows you to clearly express your intent in the rest of your code.
Maybe something like that?!
t = Time.now
eight_am_visits = Visit.all(:conditions => ['check_in > ? and check_in < ?', Time.utc(t.year, t.month, t.day, 8), Time.utc(t.year, t.month, t.day, 8, 59)])
EDIT:
Or you can grab all visits by day and filter it in Rails:
t = Time.now
visits = Visit.all(:conditions => ['created_at > ? and created_at < ?', Time.utc(t.year, t.month, t.day - 1), Time.utc(t.year, t.month, t.day + 1)])
visits_by_hour = []
(0..23).each do |h|
visits_by_hour << visits.map {|e| e if e.created_at > Time.utc(t.year, t.month, t.day, h) && e.created_at < Time.utc(t.year, t.month, t.day, h, 59)}.count
end
And in view:
<% visits_by_hour.each_with_index do |h, v| %>
<%= "#{h}:00 - #{h}:59: #{v} visitors" %>
<% end %>
Thanks for your help Olexandr and mu, I managed to figure something out with the insight you gave me here.
I came up with this, and it seems to work:
#grab the data here, this is nice because
#I can get other stats out of it (which I don't show here)
#visits = Visit.where(:check_in => #start_date..#end_date, :check_out => #start_date..#end_date).where("check_out IS NOT NULL");
#Here we go
#visitors_present_by_hour = {}
(0..23).each do |h|
# o.o Ooooooh.... o_o Hee-hee! ^_^
#visitors_present_by_hour[h] = #visits.collect{|v| v.id if v.check_in.hour <= h and v.check_out.hour >= h}.compact.count
end
Then I can just dump out that hash in my view.
It seems the solution was a bit simpler than I thought, and doing it this way actually makes rails do the time conversions from UTC.
So, I could just collect all the visits which have hours in the hour range, then compact out the nils and count what's left. I was surprised once I hit on it. I didn't need any custom SQL at all as I thought I would (unless this is completely wrong, but it seems to be working with some test data).
Thanks guys!

How can I get all the objects inserted in the previous date in Rails?

Imagine I have a model named Score, and on day 1 I insert 5 scores, on day 2,3 and 4 no scores, and on day 5 another 4 scores. Now, I would like to perform a comparison of the number of scores inserted today ( let's imagine today is day 10 ), versus the last time scores were submitted. What would be the most optimum way of getting a list of all the scores inserted last time? In this example, it's the list of scores inserted in day 5, but I would appreciate a generic way of achieving this.
Try this:
class Score
def self.recent
# find the last score date
last_date = Score.where("created_at < ?", Time.now.beginning_of_day).
order("created_at DESC").first.try(:created_at)
return [] unless last_date.present?
where(:created_at => (last_date.beginning_of_day..
last_date.end_of_day))
end
end
Now you can get the recent scores as:
Score.recent # list of Score objects

Output array based on date (sales figures by day)

I have a table with a float called 'cost' and timestamp called'created_at'.
I would like it to output an array with the summing the costs for each particular day in the last month.
Something like:
#newarray = [] #creating the new array
month = Date.today.month # Current Month
year = Date.today.year # Current Year
counter = 1 # First Day of month
31.times do #for each day of the month (max 31)
#adding sales figures for that day
#newarray.push(Order.sum(:cost, :conditions => {:created_at => "#{year}-#{month}-#{counter}"}))
counter = counter + 1 #go onto next day
end
However this doesn't work as all the timestamps have a time as well.
Apologies in advance for the poor title, I can't seem to think of a sensible one.
You should be able to use code like the following:
sales_by_day = Order.sum(:cost,
:group => 'DATE(created_at)',
:conditions => ['DATE(created_at) > ?', 31.days.ago])
(0..30).collect { |d| sales_by_day[d.days.ago.to_date.to_s] || 0 }.reverse
This will sum the order cost by day, then create an array with index 0 being the last 24 hours. It will also take only one query, whereas your example would take 31.
To change the cut off date, replace 31.days.ago with an instance of the Time class. Documentation here: http://ruby-doc.org/core/classes/Time.html
Good luck!
This should work:
(Date.today.beginning_of_month..Date.today.end_of_month).map { |d|
Order.sum(:cost, :conditions => ['created_at >= ? AND created_at < ?', d, d+1])
}
Although I think you should try getting it using a single query, instead of making one for each day.

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