text: SELECT 1 FROM #{quote_table_name(table)} LIMIT 1)
  SELECT name FROM sqlite_master WHERE type='table' AND name='sqlite_sequence';
  SELECT 1 FROM information_schema.tables
  SELECT true FROM pg_class WHERE relname = '#{table}_id_seq';
  SELECT true FROM #{table} LIMIT 1;
  SELECT table_name FROM information_schema.tables WHERE table_schema = '#{@db_name}' AND table_rows > 0
  select table_name from information_schema.views where table_schema = '#{current_database}'
  select count(*) from schema_migrations;
  