Maps and DLXS Metadata Database files (especially, the collection information and the collection groups related information) insert a layer of abstraction between the middleware and the XPAT search engine and one between the middleware and the data itself, respectively.

• Maps are text files, with SGML markup, that link certain labels with values used by the middleware. For example, the phrase "Full text," seen in an HTML pull-down on a search page can be associated with a particular SGML region in the XPAT indexed data. For information about the structure, configuration and uses of map files, click here.
• Metadata Database: This is a MySQL database containing metadata about the collection data you intend to deliver via the DLXS middleware. Some examples of metadata stored in this database are: collection id, collection name, host for the collection data, which collections belong to which groups, what SGML regions in the data are available for searching in the simple search page, etc. For information about the structure, configuration and uses of the database files, click here.
• Broker: This CGI program produces XML responses to OAI requests from OAI service providers who harvest collection metadata. For more information on the OAI protocol, see: http://www.openarchives.org/.
• Collection Manager: This CGI program, delivered as part of the DLXS installation, is used by collection managers to enter and edit information in the metadata database.
• Name Resolver: This CGI program assists in creating short, permanent URLs for longer, semi-permanent CGI URLs.
• SRU: This CGI program produces XML responses to SRU requests as dictated by SRU protocol. For more information on the SRU protocol, see: http://www.loc.gov/standards/sru/.
• DB Upgrade (e.g., upgrade_5_6): This Perl program (included in DLXS software beginning with Release #9) is used to convert your current metadata into a new database structure whenever a new DLXS middleware release requires such a conversion.
• DB Move (dbmove): This Perl program is used prior to release 13, deprecated to move a DLXS database from one type of database store (CSV) to another (MySQL).
• DB Convert (dbconv): This Perl program is used to merge the data in the legacy (before release #8 of DLXS, deprecated) groups and collections information tab-delimited files into CSV tables described in the collection manager documentation section.