
OLTP databases contain detailed and current data. An OLTP Data Warehouse System contains current and detailed data and is maintained in the schemas in the entity model (3NF).Ī Day-to-Day transaction system in a retail store, where the customer records are inserted, updated and deleted on a daily basis. For an OLTP system, the number of transactions per second measures the effectiveness. It controls data integrity in multi-access environments. Whereas, in an OLTP system, an effective measure is the processing time of short transactions and is very less. In an OLTP system, there are a large number of short online transactions such as INSERT, UPDATE, and DELETE. In a Data warehouse you can see data for 3 months, 6 months, 1 year, 5 years, etc.įirstly, OLTP stands for Online Transaction Processing, while OLAP stands for Online Analytical Processing Time Variant − A DW system contains historical data as compared to Transactional system which contains only current data. It means when data is loaded in DW system, it is not altered. Non Volatile − Data in data warehouse is non-volatile. Integrated − Data from multiple data sources are integrated in a Data Warehouse. Subject Oriented − In a DW system, the data is categorized and stored by a business subject rather than by application like equity plans, shares, loans, etc. The following are the key characteristics of a Data Warehouse − The following illustration shows the common architecture of a Data Warehouse System. The data in a DW system is accessed by BI users and used for reporting and analysis. This is used to perform BI reporting by end users. As multiple data sources are available for extraction at different time zones, staging area is used to store the data and later to apply transformations on data. Staging area is used to perform data cleansing, data transformation and loading data from different sources to a data warehouse. It consists of Operational Data Store and Staging area. It involves various data sources and operational transaction systems, flat files, applications, etc. It defines how the data comes to a Data Warehouse. A Data Warehouse has a 3-layer architecture − Data Source Layer Concurrency control and recovery mechanisms are required to maintain consistency of the database.Īn Operational Database query allows to read and modify operations (insert, delete and Update) while an OLAP query needs only read-only access of stored data (Select statement).ĭata Warehousing involves data cleaning, data integration, and data consolidations. However, Data Warehouse transactions are more complex and present a general form of data.Īn Operational System contains the current data of an organization and Data warehouse normally contains the historical data.Īn Operational Database supports parallel processing of multiple transactions. The differences between a Data Warehouse and Operational Database are as follows −Īn Operational System is designed for known workloads and transactions like updating a user record, searching a record, etc. The data in a DW system is used for different types of analytical reporting range from Quarterly to Annual comparison. A DW system is always kept separate from an operational transaction system. Normally a DW system stores 5-10 years of historical data. A DW system stores both current and historical data.

It is a central data repository where data is stored from one or more heterogeneous data sources. This is used for decision making by Business Users, Sales Manager, Analysts to define future strategy. Common data sources for a data warehouse includes −ĭata in data warehouse is accessed by BI (Business Intelligence) users for Analytical Reporting, Data Mining and Analysis. In the above image, you can see that the data is coming from multiple heterogeneous data sources to a Data Warehouse. The data in DW system is used for Analytical reporting, which is later used by Business Analysts, Sales Managers or Knowledge workers for decision-making. It may pass through operational data store or other transformations before it is loaded to the DW system for information processing.Ī Data Warehouse is used for reporting and analyzing of information and stores both historical and current data. The data in a DW system is loaded from operational transaction systems like −


A Data Warehouse is always kept separate from an Operational Database. The term Data Warehouse was first invented by Bill Inmom in 1990. Data Warehouse is a central place where data is stored from different data sources and applications. A Data Warehouse consists of data from multiple heterogeneous data sources and is used for analytical reporting and decision making.
