What is Data Warehousing?

An organization may have a number of different systems like TPS, ERP, Accounting Systems and so on. Each of these systems collect data but the data collected through these systems are not always in the same format. So we need to combine all these data from different sources into a single standard form and this process of combining multiple databases into a single homogenous form is called data warehousing.

A data warehouse is a subject-oriented, integrated, time-variant and non-volatile collection of data in support of management’s decision making process.Subject-oriented

The data in the data warehouse is organized so that all the data elements relating to the same real-world event or object are linked together.

Time-variant

The changes to the data in the data warehouse are tracked and recorded so that reports can be produced showing changes over time.

Non-volatile

Data in the data warehouse is never over-written or deleted - once committed, the data is static, read-only, and retained for future reporting.

Integrated

The data warehouse contains data from most or all of an organization's operational systems and this data is made consistent.