“The Versioned Dimensional Model” (VDM) originated in 1991, before dimensional modeling was publicized by Kimball. The earliest publications (1992) were in the Relational Journal (Codd and Date’s Relational Institute) and later through the 90s in trade magazines and presented in conferences. Since 2000 various white papers and reports have been only available to existing and prospective customers upon request.
In order to facilitate the easy management of files we propose one of two methods of setting up the environment.
Moving Files Through Directories
Under this approach, files are moved into a landing directory. When the files are ready for processing, they are moved again to a directory that is monitored by demon processes which recognize the file, chose the correct channel the file should be processed in and invoke the vdmetl command to process it. After the processing is complete, the file is moved to a "check" directory and from there to the archive.
The Hadoop Distributed File System (HDFS) uses divide and conquer techniques behind the covers to distribute data and processing. The design of HDFS according to "Tom White - The Definitive Guide to Hadoop - O'Reiley" is driven by three primary objectives: