Data Warehouse
A data warehouse (DW) or enterprise data warehouse (EDW) is a centralized data storage system designed to aggregate, store, and consolidate large volumes of data from various sources within an organization. Unlike databases that are transactional and focused on the efficient writing and reading of individual records, data warehouses are designed for query and analysis, making them ideal for business intelligence (BI) activities. They support analytical reporting, structured and/or ad hoc queries, and decision making.
Data warehouses are built by extracting data from various sources, transforming the data to fit operational needs (which can include cleaning, deduplication, and consolidation), and loading it into the warehouse. This process is known as ETL (Extract, Transform, Load). Data warehouses can contain historical data derived from transaction data, but they can include data from other sources. They are designed to give a long-range view of data over time, making them a critical component of business strategy through data analytics.
A retail chain might use a data warehouse to integrate sales data from its online store, physical stores, and third-party sellers. This integrated data can be analyzed to identify sales trends, optimize inventory management, and improve customer relationship management across all sales channels.
By storing historical sales data, the company can also perform year-over-year comparisons and seasonal trend analysis to better inform business strategies and marketing campaigns.