I want to get all records where the created_at field is less than today (a date). Is there anything like:
MyTable.find_by_created_at(< 2.days.ago)
Using ActiveRecord the standard way:
MyModel.where("created_at < ?", 2.days.ago)
Using the underlying Arel interface:
MyModel.where(MyModel.arel_table[:created_at].lt(2.days.ago))
Using some thin layer over Arel:
MyModel.where(MyModel[:created_at] < 2.days.ago)
Using squeel:
MyModel.where { created_at < 2.days.ago }
To get all records of MyTable
created up until 2 days ago:
MyTable.where(created_at: Date.new..2.days.ago)
Note that you can also look for records with fields containing fields in the future in similar way, i.e. to get all records of MyTable
with an event_date
at least 2 days from now:
MyTable.where(event_date: 2.days.from_now..DateTime::Infinity.new)
Another way is to create a scope in MyModel
or in ApplicationRecord
using the Arel interface like tokland sugensted in his answer like so:
scope :col, ->(column, predication, *args) { where(arel_table[column].public_send(predication, *args)) }
Example usage of the scope:
MyModel.col(:created_at, :lt, 2.days.ago)
For all predications, check the documentation or source code. This scope doesn't break the where
chain. This means you can also do:
MyModel.custom_scope1.col(:created_at, :lt, 2.days.ago).col(:updated_at, :gt, 2.days.ago).custom_scope2