Paper Title
DATA WAREHOUSING

Abstract
This paper presents the concepts and Introductions to Data warehousing,sources and environments for data warehousings. Keywords - flow of data,databases,sourcesystem,optimized INTRODUCTION:- The concepts of data warehousing dates back to late 1980s. In essence the data warehousing concepts was intended to provide an architectural model for the flow of data from operational systems to decision support environment . The concepts attempted to address the various problems associated with this flow mainly the high costs associated with it. In computing a data warehouse (DW or DWH) is also known as enterprise data warehouse (EDW) is a system used for reporting and data analysis and is a core component of business intelligence. Data warehouse are central repositories of data integrated from disparate sources they store current and historical data organized so as to make it easy to create reports query and get insight from the data. Unlike databases they intended to be used by analysts to help make organisational decisions. The data stored in the warehouse are uploaded from the operational systems the data may pass through an operational data store and may require data cleansing for additional operations to ensure data quality before it is used in the data warehouse for reporting. The two main approaches for building a datawarehouse system are extract ,transform ,load and extract load,transform. The environment for datawarehouseinclude the following :- Source system of data(operational databases such as relational databases. Data integration technology and processes to extract data from source systems transform them and load them into a datawarehouse. Data,data quality and governance processes. Data warehouses are optimized for analytic access pattern ,which usually involves selecting specific field rather than all fields as it common in operational databases. In absence of data warehousing and enormous amount of redundancy was required to support multiple decisions support environments. CONCLUSION:- The paper focuses on Data warehousing,sources and flow of datas. REFERENCES:- [1] Inmon,Bill(1992)”,Building the data warehouse[↑]”,wileyISBN 0-471-56960-7. [2] ]Hartner (2005)”,of data warehouses”,operational data stores and data outhouses [3] Kimball,Ralph(2011)”,The data warehouses “,wiley,237,ISBN 978-0-470-14977-5. [4] Kempe,shannon(2012)”,A short history of data warehousing [→+]”,Dataversity,retrieved.