Datetime field using Rails on Postgres

Question

I'm using Rails to make a scheduling app with Postgres. I have a model Shift with two timedate columns, start_at and end_at. The migration to create it follows:

class CreateShifts < ActiveRecord::Migration
  def change
    create_table :shifts do |t|
      t.references :user
      t.references :schedule
      t.datetime :start_at
      t.datetime :end_at
      t.string :position
      t.string :notes

      t.timestamps
    end
    add_index :shifts, :user_id
    add_index :shifts, :schedule_id
  end
end

When I try to create a record I get the following error 500 output:

GError: ERROR:  column "end_at" is of type timestamp without time zone but expression is of type time without time zone at character 132
HINT:  You will need to rewrite or cast the expression.
: INSERT INTO "shifts" ("created_at", "end_at", "notes", "position", "schedule_id", "start_at", "updated_at", "user_id") VALUES ($1, $2, $3, $4, $5, $6, $7, $8) RETURNING "id"

I am creating a valid DateTime object before the DB save, because I've used the logger to display it and it is correct. The params look like this:

{"utf8"=>"✓",
 "authenticity_token"=>"qornHMTAdikZJP/sByPIg//fFuYHHAQH3M/0R9XnP+o=",
 "shift"=>{"user_id"=>"1",
 "start_at(1i)"=>"2011",
 "start_at(2i)"=>"11",
 "start_at(3i)"=>"14",
 "start_at(4i)"=>"00",
 "start_at(5i)"=>"01",
 "end_at(1i)"=>"2011",
 "end_at(2i)"=>"11",
 "end_at(3i)"=>"14",
 "end_at(4i)"=>"00",
 "end_at(5i)"=>"02",
 "position"=>"",
 "notes"=>""},
 "schedule_id"=>"1"}

However, I can create a record via console by setting both fields to Time.now.

Answer 1

The error message is quite clear: Your $2 in the INSERT statement is of type time instead of type timestamp (datetime)

INSERT INTO "shifts"

("created_at", "end_at", "notes", "position", "schedule_id", "start_at", "updated_at", "user_id")

VALUES ($1, $2, $3, $4, $5, $6, $7, $8) RETURNING "id"

Emphasis mine. You must be mixing up parameters, $2 is obviously not the one you display at the end of your posting. Or you inadvertently cast it to time before assigning. The part where you assign $2 is not visible in the question, that is where the problem occurs, most likely.

Maybe some kind of typo like in your question where you mention timedate instead of datetime?