Dimensional modeling ( DM ) is part of the Business Dimensional Lifecycle methodology developed by Ralph Kimball which includes a set of methods, techniques and concepts for use in data warehouse design. The approach focuses on identifying the key business processes within a business and modelling and implementing these first before adding additional business processes, as a bottom-up approach . An alternative approach from Inmon advocates a top down design of the model of all the enterprise data using tools such as entity-relationship modeling (ER).
20-572: (Redirected from Dm ) [REDACTED] Look up DM or dm in Wiktionary, the free dictionary. DM , Dm , dm , or D.M. may stand for: Academic titles and postnominals [ edit ] Doctor of Management , an academic management degree Doctor of Music , an academic music-performance degree, also known as DMA Arts, entertainment, and media [ edit ] Broadcasting [ edit ] Danger Mouse (TV series) ,
40-569: A British animated television series WWDM , a radio station licensed to Sumter, South Carolina, United States Gaming [ edit ] Deathmatch (video games) , a gameplay mode integrated into first-person shooter computer games Dungeon Master , the game designer, storyteller and referee in Dungeons & Dragons Music [ edit ] D minor , a minor scale or chord DM (album) , 2017, by Mexican singer Dulce María "DM" (song) , 2022, by fromis_9 Dance marathon ,
60-499: A chemical agent used in riot control Differential Manchester encoding Distributed morphology , a theoretical framework in linguistics Sports and recreation [ edit ] Dallas Mavericks , an NBA team Danske Mesterskaber , the Danish Athletics Championships Defensive midfielder , an association football position Divemaster , in scuba diving Dungeon monitor ,
80-429: A multiple-day charity event on U.S. college campuses Depeche Mode , an English synthpop band formed in 1980 Drum major (marching band) , the leader of a marching band Death Metal , an extreme subgenre of heavy metal music Social media [ edit ] Digital marketing Private message (also direct message or dm ) In business and economics [ edit ] Deutsche Mark (1948–2002),
100-642: A safety role in BDSM Other uses [ edit ] De minimis , a Latin legal term Diis Manibus , a Latin epitaphial acronym SJ Dm3 , and Dm, Swedish locomotives District magistrate , senior local role in the Indian Administrative Service Des Moines, Iowa See also [ edit ] DMS (disambiguation) MD (disambiguation) Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with
120-466: A set of techniques and concepts used in data warehouse design Software [ edit ] Display Manager , a window system for Domain/OS on Apollo/Domain workstations Device mapper , a component of the Linux kernel that supports logical volume management X display manager , a graphical login manager Medicine [ edit ] Degenerative myelopathy , a condition in dogs affecting
140-693: A soldier fulfilling the marksman role in an infantry squad Royal Naval Armaments Depot , Defense Munitions, sites are prefixed DM A US Navy hull classification symbol: Light minelayer (DM) Places [ edit ] Davis–Monthan Air Force Base , Tucson, Arizona, US Des Moines, Iowa , the state capital Dominica , an island nation in the Caribbean Sea (ISO 3166-1 alpha-2 code: DM) Science, technology, and mathematics [ edit ] Computing [ edit ] .dm , Dominica's top-level Internet domain Dimensional modeling ,
160-419: Is oriented around understandability and performance. The dimensional model is built on a star-like schema or snowflake schema , with dimensions surrounding the fact table. To build the schema, the following design model is used: The process of dimensional modeling builds on a 4-step design method that helps to ensure the usability of the dimensional model and the use of the data warehouse . The basics in
180-536: The Unified Modeling Language |UML). After describing the business process, the next step in the design is to declare the grain of the model. The grain of the model is the exact description of what the dimensional model should be focusing on. This could for instance be “An individual line item on a customer slip from a retail store”. To clarify what the grain means, you should pick the central process and describe it with one sentence. Furthermore,
200-429: The concepts of facts (measures), and dimensions (context). Facts are typically (but not always) numeric values that can be aggregated, and dimensions are groups of hierarchies and descriptors that define the facts. For example, sales amount is a fact; timestamp, product, register#, store#, etc. are elements of dimensions. Dimensional models are built by business process area, e.g. store sales, inventory, claims, etc. Because
220-414: The design build on the actual business process which the data warehouse should cover. Therefore, the first step in the model is to describe the business process which the model builds on. This could for instance be a sales situation in a retail store. To describe the business process, one can choose to do this in plain text or use basic Business Process Model and Notation (BPMN) or other design guides like
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#1732782565325240-450: The different business process areas share some but not all dimensions, efficiency in design, operation, and consistency, is achieved using conformed dimensions , i.e. using one copy of the shared dimension across subject areas. Dimensional modeling does not necessarily involve a relational database. The same modeling approach, at the logical level, can be used for any physical form, such as multidimensional database or even flat files. It
260-482: The former currency of Germany (and West Germany) East German mark (1951–1990) Companies and products [ edit ] Detroit and Mackinac Railway dm-drogerie markt , a German drugstore chain Dr. Martens , a brand of boots DM, IATA code of Arajet DM, then IATA code of Maersk Air , a former Danish airline which operated from 1969 until 2005 Military [ edit ] Designated marksman ,
280-410: The foundation of the fact table, and is where the data for the fact table is collected. Typically dimensions are nouns like date, store, inventory etc. These dimensions are where all the data is stored. For example, the date dimension could contain data such as year, month and weekday. After defining the dimensions, the next step in the process is to make keys for the fact table. This step is to identify
300-431: The grain (sentence) is what you are going to build your dimensions and fact table from. You might find it necessary to go back to this step to alter the grain due to new information gained on what your model is supposed to be able to deliver. The third step in the design process is to define the dimensions of the model. The dimensions must be defined within the grain from the second step of the 4-step process. Dimensions are
320-474: The normal flatten de-normalized dimensions. Dimensions are strictly joined together in sub dimensions. Snowflaking has an influence on the data structure that differs from many philosophies of data warehouses. Single data (fact) table surrounded by multiple descriptive (dimension) tables Developers often don't normalize dimensions due to several reasons: There are some arguments on why normalization can be useful. It can be an advantage when part of hierarchy
340-402: The numeric facts that will populate each fact table row. This step is closely related to the business users of the system, since this is where they get access to data stored in the data warehouse . Therefore, most of the fact table rows are numerical, additive figures such as quantity or cost per unit, etc. Dimensional normalization or snowflaking removes redundant attributes, which are known in
360-531: The skin, muscles, and other organs Physics [ edit ] Dark matter , in cosmology, hypothetical non-luminous matter Deformable mirror Dispersion measure , the amount of dispersion of radio waves by interstellar medium Units of length [ edit ] Decimetre ( dm ), equal to ten centimetres Decametre (sometimes Dm ), equal to ten metres Data mile ( DM ), in radar, equal to 6000 feet Other uses in science, technology and mathematics [ edit ] Adamsite ,
380-514: The spinal cord Diabetes mellitus , a disease characterized by high blood sugar Difference due to memory , a neural activity effect Diminished motivation , a condition characterized by lack of motivation Double minute , fragments of extrachromosomal DNA in human tumors Myotonic dystrophy (DM-1/2/3), a chronic muscle-wasting disease n-Decyl β-D-Maltopyranoside, a maltoside detergent used when purifying membrane proteins Dermatomyositis , an inflammatory systemic disorder affecting
400-639: The title DM . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=DM&oldid=1247605009 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages DM">DM The requested page title contains unsupported characters : ">". Return to Main Page . Dimensional modeling Dimensional modeling always uses
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