A Question about Model and Database?

hi i m new to rails i need to know the => which is the best way to create Database table in Rails?

  1. rails generate model User name:string email:string
    this will create a migration file with something like this
class CreateUsers < ActiveRecord::Migration
  def change
    create_table :users do |t|
      t.string :name # *see here name column is already made becoz we have passed a parameters*
      t.string :email # *same as above*

      t.timestamps
    end
  end
end

this is one method
2) rails generate model Page
this will create a empty migration file something like this

class CreatePages < ActiveRecord::Migration
  def change
    create_table :users do |t|
      ===>> *now we can add here like **t.string "name"** to create column manually* ========>>>>>
t.timestamps
    end
  end
end

So which is the good way to do above things example 1 or example 2?
Please tell.
and if i have to write a drop_table method in migration, can i write in the way which i showed below
class CreateSubjects < ActiveRecord::Migration
def change
create_table :subjects do |t|
t.string “name”

  t.timestamps
end

end

def self.down
drop_table :subjects
end
end
So again same question which is the good way to do above things example 1 ( model with parameter ) or example 2 ( model without parameter )?
Thanks for Taking Time to Read.

please help me

Rails is smart enough to determine if you want to create or drop a table if you have done the migration with change

def change

#code here

end

it only depends on how you write the commands

if you do

rake db:migrate

then it will create the db (if the code inside change is about it) and if you do

rake db:rollback

it will drop that table

in other case then

def up

#create table here

end

def down

#drop table here

end

take a look here

http://guides.rubyonrails.org/migrations.html

and then here

http://stackoverflow.com/questions/10365129/rails-migrations-self-up-and-self-down-versus-change

http://stackoverflow.com/questions/7600415/rails-3-generate-migration-no-up-or-down-method

there is a lot more on google

JavierQ

use def change

forget up and down def

cheers

Fahim Babar Patel

thanks for reply

It is entirely up to you, do whichever you prefer.

Colin