A mapping mechanism for a primary B+tree in a database management system. The bodies define at least one pair of respective roller guide tracks thereon. For a pixel of an overlapping portion for which the liquid is ejected from the first and second heads, a tone value of the first color space is converted to a tone value of the second color space according to a third color conversion table created based on the first and second color conversion tables. The method further includes removing the spacers to form gaps, and implanting a halo extension through the gaps and into an underlying diffusion region. System with storage medium and terminal and non-volatile, application-independent restore module. The information retrieved by the CPU is displayed on the display unit, and data can be retrieved without the user performing an input operation by using a keyboard or the like.