database_exists?

# File activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb, line 101
      def self.database_exists?(config)
        config = config.symbolize_keys
        if config[:database] == ":memory:"
          return true
        else
          database_file = defined?(Rails.root) ? File.expand_path(config[:database], Rails.root) : config[:database]
          File.exist?(database_file)
        end
      end