Business Intelligence Dictionary: Data Marts Explained | NSBI
Having explained what a Data Warehouse is you should be now aware that it is not well optimized to serve a particular need but rather consolidate the whole historical data of an organization. This implies a number of issues when trying to maximize performance for particular usage. Here come Data Marts.
Data Mart | Definition
NSBI Dictionary defines a Data Mart as a physical repository of DWH data that is designed and optimized to serve a particular community of knowledge workers. We may simplify the definition even further as saying that a Data Mart is a smaller section of the Data Warehouse that uses only the data required in a specific business unit (department).
Note: Even though we defined Data Marts as physical repositories (physically available on a data server), there are also virtual Data Marts that are simply logical structures that do not physically exist, but are pre-compiled at runtime (and/or cached).
NSBI Tutorials aim to make Business Intelligence (BI) and Data Warehousing (DWH) attractive to non-technical people as well as to those who are now entering the field and are excited by the numerous ways data is changing our world. NSBI Tutorials are written and delivered by Nick Shopov, (BI Software Developer & DWH Consultant).
Data Mart | Example
Consider a huge financial institution - a bank. It aggregates data from various operational databases - serving (a) chequing deposits, (b) savings deposits, (c) individual loans, (d) mortgages, (e) sovereign bonds, etc.
All these systems are loaded into a Data Warehouse but a specific department only deals with deposits. In order to optimize the analysis and reporting for this specific community of knowledge workers we create a designated Data Mart that will include only those facts and dimensions required for this department.