1. A method for retrieving data in a relational database, comprising: accessing by using a computer system the relational database to obtain information regarding a unit of manufacture, the relational database comprising at least one location information lookup table, at least one parts information lookup table, at least one unit storage table, and at least one parameter definition lookup table; retrieving information on the unit of manufacture from at least a portion of the relational database; wherein said at least one location information lookup table of the relational database comprises: a list of available locations in the unit of manufacture to place a part from the at least one parts information lookup table; and information indicating, for each location of a plurality of available locations in the unit of manufacture, whether the location is required to be populated by a part corresponding to an entry in said at least one parts information lookup table; wherein said at least one parts information lookup table comprises entries for a plurality of parts usable in different types of units of manufactures; and wherein said at least one unit storage table of the relational database specifies a configuration of the unit of manufacture and comprises: a unit parts list storage table containing information indicating a list of parts for the unit of manufacture, and further containing, for each part in the list of parts, information usable to determine at least one location within the unit of manufacture at that part is placed; and a unit parameter list storage table containing information regarding one or more values for one or more parameters of one or more parts in the unit parts list storage table, wherein the one or more parameters are adjustable settings for the one or more parts; assigning one or more default values to the one or more parameters, wherein the one or more default values are predefined values specified by one or more entries for the one or more parts in the parameter definition lookup table of the relational database; and subsequently modifying one or more values for the one or more parameters, wherein said modifying does not affect the predefined values specified by the parameter definition lookup table; wherein the relational database further comprises an interface definition lookup table that defines interfaces for a plurality of parts in the parts information lookup table, wherein the interfaces are potential locations for electrical or mechanical connections between parts; and wherein the relational database further comprises a parameter list lookup table and a parameter description look up table that are usable to access information indicating multiple pre-defined configurations of a part listed in the unit parts list storage table.