# File lib/active_record/vendor/db2.rb, line 128
    def prepare(sql)
      @sql = sql
      check_rc(SQLPrepare(@handle, sql))
      rc, @numParms = SQLNumParams(@handle) #number of question marks
      check_rc(rc)
      #--------------------------------------------------------------------------
      # parameter attributes are stored in instance variable @parmArray so that
      # they are available when execute method is called.
      #--------------------------------------------------------------------------
      if @numParms > 0           # get parameter marker attributes
        1.upto(@numParms) do |i| # parameter number starts from 1
          rc, type, size, decimalDigits = SQLDescribeParam(@handle, i)
          check_rc(rc)
          @parmArray << Parameter.new(type, size, decimalDigits)
        end
      end
      @prepared = true
      self
    end