Difference between postgresql time and rails 3 app time - ruby-on-rails-3

Question

Scenario: I want to get the nearest time in relation to my system time.
I have written the following method inside my model:
def self.nearest_class(day, teacher_id, hour_min)
day_of_week = '%' + day + '%'
if hour_min == "06:00:00"
where('frequency like ? AND teacher_id = ? AND (start_time >= ?)', day_of_week, teacher_id, hour_min).order('start_time ASC')
else
where('frequency like ? AND teacher_id = ? AND (start_time >= localtime(0))', day_of_week, teacher_id).order('start_time ASC')
end
end
When I tested the above method in rails console using Lecture.nearest_class('Monday', 1, 'localtime(0)'), the following query was returned together with some data:
SELECT "lectures".* FROM "lectures" WHERE (frequency like '%Monday%' AND teacher_id = 1 AND (start_time >= localtime(0))) ORDER BY start_time ASC
But I am expecting no record because my system time is greater than any start_time recorded in the database. I have used the query from the console to pgadmin3 to test if the results are same. However, pgadmin3 showed no results, as expected.
Are there differences in postgresql time and rails app time? How can I be able to check these differences? I tried Time.now in the console and it is the same as SELECT LOCALTIME(0) from pgadmin3. What should be the proper way to get the records for nearest system time?
To further set the context, here's my controller method:
def showlectures
#teacher = Teacher.login(params[:id]).first
#lecture_by_course = nil
if #teacher
WEEKDAY.each do |day|
hour_min = "06:00:00"
if day == Time.now.strftime("%A") # check if day of week is same e.g. 'Monday'
hour_min = "localtime(0)" # system time with format: HH:MM:SS
end
#lecture_by_course = Lecture.nearest_class(day, #teacher.id, hour_min).first
if #lecture_by_course
break
end
end
end
render json: #lecture_by_course, include: { course: { only: [:name, :id] }}
end

Answer 1

I solved this by just passing the server Time.now instead of having a SQL check. { :| d'oh }