default_value

# File activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb, line 470
        def default_value(value)
          # Boolean types
          return "t" if value =~ /true/i
          return "f" if value =~ /false/i
          
          # Char/String type values
          return $1 if value =~ /^'(.*)'::(bpchar|text|character varying)$/
          
          # Numeric values
          return value if value =~ /^[0-9]+(\.[0-9]*)?/

          # Date / Time magic values
          return Time.now.to_s if value =~ /^now\(\)|^\('now'::text\)::(date|timestamp)/i

          # Fixed dates / times
          return $1 if value =~ /^'(.+)'::(date|timestamp)/
          
          # Anything else is blank, some user type, or some function
          # and we can't know the value of that, so return nil.
          return nil
        end