Data Warehousing

In data warehousing, data is collected from multiple sources and then stored in a central location called a data warehouse. Data warehouses are used to support decision making by providing users with access to data that would otherwise be difficult or impossible to obtain. Data warehouses typically contain data that is several years old, but they can also contain real-time data.

Data warehouses are designed to provide easy access to data by using a star schema or a snowflake schema. In a star schema, each dimension is represented by a single table, and the fact table contains the data that is being analyzed. In a snowflake schema, the dimensions are represented by multiple tables, and the fact table contains the data that is being analyzed.

Data warehouses can be used for a variety of purposes, such as business intelligence, data mining, and trend analysis.