Defaulting datetime in migrations

Rails
1

I have the following in a migration:

create_table :orders do |t|
t.references :cart
t.references :user
t.float :item_total, :default => 0.0, :null => false
t.float :discount, :default => 0.0, :null => false
t.float :tax, :default => 0.0, :null => false
t.string :shipping_type
t.float :shipping_cost, :default => 0.0, :null => false
t.float :total, :default => 0.0, :null => false
t.string :tracking
t.datetime :placed_at, :default => ‘0000-00-00 00:00:00’, :null
=> false
t.datetime :shipped_at, :default => ‘0000-00-00 00:00:00’, :null
=> false

  t.timestamps
end

But when I look at scheme.rb I see:

create_table “orders”, :force => true do |t|
t.integer “cart_id”
t.integer “user_id”
t.float “item_total”, :default => 0.0, :null => false
t.float “discount”, :default => 0.0, :null => false
t.float “tax”, :default => 0.0, :null => false
t.string “shipping_type”
t.float “shipping_cost”, :default => 0.0, :null => false
t.float “total”, :default => 0.0, :null => false
t.string “tracking”
t.datetime “placed_at”, :null => false
t.datetime “shipped_at”, :null => false
t.datetime “created_at”
t.datetime “updated_at”
end

As you can see, the “default” value did not take. Yet it did for the
floats that default to 0.0

When I try to save an object of class order I get errors saying the
placed_at and shipped_at can not be null. (Which makes sense giving
what I’ve pasted above).

How can I make those two fields default to “0000-00-00 00:00:00”?

Thanks,
Greg

2

several possible problems here:

not sure, but maybe you would need to provide a DateTime object instead
of a string.

But however, 0000-00-00 isn’t a valid date anyway, since there is
neither a month 0 nor such a day. It should be 0000-01-01

3

On Sat, May 31, 2008 at 12:06 AM, Greg [email protected] wrote:

How can I make those two fields default to “0000-00-00 00:00:00”?

The migration might not do it as the migration supports all base
databases
(mysql, postgres and sqlite3). Mysql and Postgres both can take
defaults on
a date/time type column, I am not sure on sqlite3, that could be the
problem.

If you must do this, then you can just do some sql in the migration:

sql = “SOME SQL STATEMENT TO SET THE DEFAULT YOU WANT”
execute(sql)

You can look at http://dev.mysql.com/doc/refman/5.0/en/timestamp.html
for
mysql or
http://www.postgresql.org/docs/8.0/interactive/functions-datetime.html
for
postgres.

Mikel

4

Well, nothing I’ve tried has worked as far as the migration goes. So
now I’m trying in the model. I have:

class Order < ActiveRecord::Base

before_validation_on_create :assign_dates

validates_presence_of :placed_at
validates_presence_of :shipped_at

private

def assign_dates
self.placed_at = ‘0000-00-00 00:00:00’
self.shipped_at = ‘0000-00-00 00:00:00’
end

end

But when I do a create! action I get: “Validation failed: Shipped at
can’t be blank, Placed at can’t be blank”

Why aren’t those two values being set before validation occurs?

Greg

5

Why aren’t those two values being set before validation occurs?

as mentioneb above: 0000-00-00 isn’t a valid date in any case

Rails may try to convert this string into a DateTime object with
DateTime.parse or something on that line and that will fail for
0000-00-00.

6

Ok, setting the date to a valid date “2000-01-01 00:00:00” in the
“assign_dates” method worked. I guess I’m just so used to dealing with
MyPHPAdmin when using PHP - it’s defaults date, datetime and time
fields to all zeros and seems to just always treat them as strings.

Thanks!
Greg