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

Accepted answer with Postgres db:

namespace :db do
  desc "Truncate all tables"
  task :truncate => :environment do
    conn = ActiveRecord::Base.connection
    postgres = "SELECT tablename FROM pg_catalog.pg_tables WHERE schemaname='public'"
    tables = conn.execute(postgres).map { |r| r['tablename'] }
    tables.delete "schema_migrations"
    tables.each { |t| conn.execute("TRUNCATE \"#{t}\"") }
  end
end

If there are foreign_key error like ActiveRecord::StatementInvalid (PG::FeatureNotSupported: ERROR: cannot truncate a table referenced in a foreign key constraint)

Then, CASCADE option would help.

tables.each { |t| conn.execute("TRUNCATE \"#{t}\" CASCADE") }