Class ActiveRecord::ConnectionAdapters::AbstractAdapter
In: activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
Parent: Object

All the concrete database adapters follow the interface laid down in this class. You can use this interface directly by borrowing the database connection from the Base with Base.connection.

Most of the methods in the adapter are useful during migrations. Most notably, SchemaStatements#create_table, SchemaStatements#drop_table, SchemaStatements#add_index, SchemaStatements#remove_index, SchemaStatements#add_column, SchemaStatements#change_column and SchemaStatements#remove_column are very useful.

Methods

active?   adapter_name   disconnect!   format_log_entry   log   log_info   prefetch_primary_key?   raw_connection   reconnect!   requires_reloading?   supports_count_distinct?   supports_migrations?   verify!  

Included Modules

Quoting DatabaseStatements SchemaStatements QueryCache

Public Instance methods

active?()

Is this connection active and ready to perform queries?

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 70
      def active?
        @active != false
      end
adapter_name()

Returns the human-readable name of the adapter. Use mixed case - one can always use downcase if needed.

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 37
      def adapter_name
        'Abstract'
      end
disconnect!()

Close this connection

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 80
      def disconnect!
        @active = false
      end
log_info(sql, name, runtime)

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 107
      def log_info(sql, name, runtime)
        if @logger && @logger.debug?
          name = "#{name.nil? ? "SQL" : name} (#{sprintf("%f", runtime)})"
          @logger.debug format_log_entry(name, sql.squeeze(' '))
        end
      end
prefetch_primary_key?(table_name = nil)

Should primary key values be selected from their corresponding sequence before the insert statement? If true, next_sequence_value is called before each insert to set the record’s primary key. This is false for all adapters but Firebird.

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 57
      def prefetch_primary_key?(table_name = nil)
        false
      end
raw_connection()

Provides access to the underlying database connection. Useful for when you need to call a proprietary method such as postgresql’s lo_* methods

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 103
      def raw_connection
        @connection
      end
reconnect!()

Close this connection and open a new one in its place.

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 75
      def reconnect!
        @active = true
      end
requires_reloading?()

Returns true if its safe to reload the connection between requests for development mode. This is not the case for Ruby/MySQL and it’s not necessary for any adapters except SQLite.

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 86
      def requires_reloading?
        false
      end
supports_count_distinct?()

Does this adapter support using DISTINCT within COUNT? This is true for all adapters except sqlite.

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 49
      def supports_count_distinct?
        true
      end
supports_migrations?()

Does this adapter support migrations? Backend specific, as the abstract adapter always returns false.

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 43
      def supports_migrations?
        false
      end
verify!(timeout)

Lazily verify this connection, calling +active?+ only if it hasn’t been called for timeout seconds.

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 92
      def verify!(timeout)
        now = Time.now.to_i
        if (now - @last_verification) > timeout
          reconnect! unless active?
          @last_verification = now
        end
      end

Protected Instance methods

format_log_entry(message, dump = nil)

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 140
        def format_log_entry(message, dump = nil)
          if ActiveRecord::Base.colorize_logging
            if @@row_even
              @@row_even = false
              message_color, dump_color = "4;36;1", "0;1"
            else
              @@row_even = true
              message_color, dump_color = "4;35;1", "0"
            end

            log_entry = "  \e[#{message_color}m#{message}\e[0m   "
            log_entry << "\e[#{dump_color}m%#{String === dump ? 's' : 'p'}\e[0m" % dump if dump
            log_entry
          else
            "%s  %s" % [message, dump]
          end
        end
log(sql, name) {|| ...}

[Source]

# File activerecord/lib/active_record/connection_adapters/abstract_adapter.rb, line 115
        def log(sql, name)
          if block_given?
            if @logger and @logger.level <= Logger::INFO
              result = nil
              seconds = Benchmark.realtime { result = yield }
              @runtime += seconds
              log_info(sql, name, seconds)
              result
            else
              yield
            end
          else
            log_info(sql, name, 0)
            nil
          end
        rescue Exception => e
          # Log message and raise exception.
          # Set last_verification to 0, so that connection gets verified
          # upon reentering the request loop
          @last_verification = 0
          message = "#{e.class.name}: #{e.message}: #{sql}"
          log_info(message, name, 0)
          raise ActiveRecord::StatementInvalid, message
        end

[Validate]