rails--rails/activerecord/lib/active_record/schema_migration.rb

51 lines
1.3 KiB
Ruby

require 'active_record/scoping/default'
require 'active_record/scoping/named'
module ActiveRecord
# This class is used to create a table that keeps track of which migrations
# have been applied to a given database. When a migration is run, its schema
# number is inserted in to the `SchemaMigration.table_name` so it doesn't need
# to be executed the next time.
class SchemaMigration < ActiveRecord::Base # :nodoc:
class << self
def primary_key
"version"
end
def table_name
"#{table_name_prefix}#{ActiveRecord::Base.schema_migrations_table_name}#{table_name_suffix}"
end
def table_exists?
ActiveSupport::Deprecation.silence { connection.table_exists?(table_name) }
end
def create_table
unless table_exists?
version_options = connection.internal_string_options_for_primary_key
connection.create_table(table_name, id: false) do |t|
t.string :version, version_options
end
end
end
def drop_table
connection.drop_table table_name, if_exists: true
end
def normalize_migration_number(number)
"%.3d" % number.to_i
end
def normalized_versions
pluck(:version).map { |v| normalize_migration_number v }
end
end
def version
super.to_i
end
end
end