DBMS (Database Management System) is the whole system used for managing digital databases, which allows storage of database content, creation/maintenance of data, search and other functionalities. A data warehouse is a place that stores data for archival, analysis and security purposes. A data warehouse is made up of a single computer or several computers connected together to form a computer system.
DBMS, sometimes just called a database manager, is a collection of computer program that is dedicated for the management (i.e. organization, storage and retrieval) of all databases that are installed in a system (i.e. hard drive or network). There are different types of Database Management Systems existing in the world, and some of them are designed for the proper management of databases configured for specific purposes. Most popular commercial Database Management Systems are Oracle, DB2 and Microsoft Access. All these products provide means of allocation of different levels of privileges for different users, making it possible for a DBMS to be controlled centrally by a single administrator or to be allocated to several different people. There are four important elements in any Database Management System. They are the modeling language, data structures, query language and mechanism for transactions. The modeling language defines the language of each database hosted in the DBMS. Currently several popular approaches like hierarchal, network, relational and object are in practice. Data structures help organize the data such as individual records, files, fields and their definitions and objects such as visual media. Data query language maintains the security of the database by monitoring login data, access rights to different users, and protocols to add data to the system. SQL is a popular query languagewhich is used in Relational Database Management Systems. Finally, the mechanism that allows for transactions help concurrency and multiplicity. That mechanism will make sure same record will not be modified by multiple users at the same time, thus keeping the data integrity in tact. Additionally, DBMSs provide backup and other facilities as well.
As mentioned earlier, data warehouse is a place that stores data for the purpose of archiving, reporting and analyzing. It can contain many different databases of an organization. Addition to being a storage place for data, a data warehouse should also have a system that would allow the user to access data easily.The functions operated by a data warehouse generally maintain three layers. First layer is the staging layer, which is used to store raw data that is used by developers for analysis. The second layer is the integration layer. It is used to integrate and to provide a level of abstraction for the users. Third level is the access layer, which provides functionalities to users to get data out. Data warehouses play a major role in Decision Support Systems (DSS). DSS is a technique used by organizations to develop and identify facts, trends or relationships that would help them to make better decisions to achieve their organizational goals.
The key difference between DBMS and data warehouse is the fact that a data warehouse can be treated as a type of a database or a special kind of database, which provides special facilities for analysis, and reporting while, DBMS is the overall system which manages a certain database. Data warehouses mainly store data for the purpose of reporting and analysis that would help an organization in the process making decisions, while a DBMS is a computer application that is used to organize, store and retrieve data. A data warehouse needs to use a DBMS to make data organization and retrieval more efficient.