rails task db:info dumps info about DB

lib/tasks/db/info.rake

@@ -0,0 +1,58 @@
+module DbInfoTask
+  extend self
+
+  IGNORE_TABLES = %w[ar_internal_metadata delayed_jobs schema_migrations seed_migration_data_migrations].freeze
+
+  def run
+    puts 'Database Info:'
+    puts "  Rails.env=#{Rails.env}"
+    puts "  adapter='#{db_config['adapter']}'"
+    puts "  database='#{db_config['database']}'"
+
+    if db_config['adapter'] != 'sqlite3'
+      puts "  host='#{db_config['host']}'"
+      puts "  user='#{db_config['username']}'"
+      puts "  password=[#{'*' * db_config['password'].to_s.length}]"
+    end
+    puts ''
+
+    table_info, max_len = read_table_info
+
+    table_info.each do |name, count|
+      count_s = count.positive? ? count : '.'
+      puts "  #{name.rjust(max_len)}  #{count_s}"
+    end
+
+    puts ''
+  end
+
+  def read_table_info
+    max_len = 0
+    table_info = []
+
+    ActiveRecord::Base.connection.tables.sort.each do |table|
+      next if IGNORE_TABLES.include?(table)
+
+      sql = "select count(*) as count from #{table}"
+      result = ActiveRecord::Base.connection.execute(sql)
+      count = result.first['count']
+
+      max_len = table.length if table.length > max_len
+      table_info << [table, count]
+    end
+
+    [ table_info, max_len ]
+  end
+
+  def db_config
+    @db_config ||= Rails.configuration.database_configuration[Rails.env]
+  end
+end
+
+namespace :db do
+  desc 'Prints out a list of tables and their counts'
+  task info: :environment do
+    DbInfoTask.run
+  end
+end
+