What do i need to do to tell Og to be careful with pre-existing ('legacy') databases, so that: 1) the schema does not get changed 2) no columns / rows / tables get dropped
Can Og determine the schema of a given MySQL Database, and automatically create a skeleton of matching Class definitions? (without relations ..)
Such a reverse engineered mode would be good for people who want to use a legacy database with Og
You just have to model the Og classes after the real tables and adapt:
class User # To use a different pk attr_accessor :id, Fixnum, :primary_key => true # custom join tables joins_many :pictures, Picture, :through => ModelPics end class ModelPics # set the sql table set_sql_table "join_table_foo" # has_ones are needed to generate the correct relations # for example specify a special foreign key has_one OgModel, :foreign_key => 'to_model' has_one Picture end class Picture end
This as an example on how to change the primary key, set sql tables, modeling join tables and using custom foreign keys.
Additional to that, if you want to forbid Og to change the Tables at all:
# Completely shut generating off Og.create_schema = false # Control generating # :add/true meaning columns get added, none removed # :full meaning columns also get removed Og.manager_options.update( :evolve_schema => :add ) # .. Og.start