class ActiveRecord::Schema

support migrations, the two features being very similar.
ActiveRecord::Schema is only supported by database adapters that also
end
add_index :posts, :author_id
end
t.boolean :private, default: false
t.text :body
t.string :subject
t.integer :author_id, null: false
create_table :posts do |t|
add_index :authors, :name, :unique
end
t.string :name, null: false
create_table :authors do |t|
ActiveRecord::Schema.define do
Usage:
databases.
directly, so your applications can more easily support multiple
DSL. This means you can define tables, indexes, etc. without using SQL
Allows programmers to programmatically define a schema in a portable
= Active Record Schema

def self.define(info={}, &block)

end
...
ActiveRecord::Schema.define(version: 20380119000001) do

about the current schema (currently, only the schema's version):
The +info+ hash is optional, and if given is used to define metadata

+add_index+, etc.).
database definition DSL to build up your schema (+create_table+,
adapter are available within the block, so you can easily use the
Eval the given block. All methods available to the current connection 
def self.define(info={}, &block)
  new.define(info, &block)
end

def define(info, &block) # :nodoc:

:nodoc: 
def define(info, &block) # :nodoc:
  instance_eval(&block)
  unless info[:version].blank?
    initialize_schema_migrations_table
    connection.assume_migrated_upto_version(info[:version], migrations_paths)
  end
end

def migrations_paths

# => ["db/migrate"] # Rails migration path by default.
ActiveRecord::Schema.new.migrations_paths

Returns the migrations paths. 
def migrations_paths
  ActiveRecord::Migrator.migrations_paths
end