How to delete all data from all tables in Rails?

Question

I can do Post.delete_all to delete all my posts, but what if I want to delete all posts, comments, blogs, etc.?

How do I iterate over all my models and

Answer 1

# fast truncation of all tables that need truncations (select is 10x faster then truncate)
# http://grosser.it/2012/07/03/rubyactiverecord-fastest-way-to-truncate-test-database/
def truncate_all_tables
  connection = ActiveRecord::Base.connection
  connection.disable_referential_integrity do
    connection.tables.each do |table_name|
      next if connection.select_value("SELECT count(*) FROM #{table_name}") == 0
      connection.execute("TRUNCATE TABLE #{table_name}")
    end
  end
end