Ruby on Rails SQL "SELECT" timing out

I am selecting records from a table named "bookings" that contains over 100,000 records. I am new to SQL and for some reason this is taking many seconds to finish, and even timing out on my production server:

def bookings_in_date_range(division, startdate, enddate)
  sql = "SELECT * FROM bookings WHERE division = '#{division}';"
  bookings = ActiveRecord::Base.connection.execute(sql) # all bookings from this division
  bookingsindaterange = bookings.select { |b| (parsedate(b["date"]) >= parsedate(startdate)) and (parsedate(b["date"]) <= parsedate(enddate)) } # refine to bookings in date range
end

def parsedate(date) # get date from mm/dd/yy format
  d = date.split("/")
  return Date.parse("#{d[2]}-#{d[0]}-#{d[1]}")
end

I also included the function I'm using to re-format the date, however executing the SQL statement appears to be where the process is hanging up, based on my tests.

My goal is to select all "bookings" in a "division" within a specified date range. Existing code works faster for divisions with low numbers of bookings.