What is Database?
A database is the organized collection of data. Most of the times, these raw data are stored in very large databases. A Database may contain different levels of abstraction in its architecture.
Typically, the three levels: external, conceptual and internal make up the database architecture.
- Used for Online Transactional Processing (OLTP) but can be used for other purposes such as Data Warehousing. This records the data from the user for history.
- The tables and joins are complex since they are normalized (for RDMS). This is done to reduce redundant data and to save storage space.
- Entity – Relational modelling techniques are used for RDMS database design.
- Optimized for a write operation.
- Performance is low for analysis queries.
A data warehouse is a repository of data that has been extracted and integrated from heterogeneous and autonomous distributed sources. The warehouse data is used for decision support or data mining.
What is Data Warehouse?
A data warehouse provides information processing by providing a solid platform of integrated, historical data from which to do analysis. The ultimate goal of data warehousing is the creation of a logical view of data that may reside in many different, separate physical databases.
The data warehouse is optimized for analysis of the large volume of data rather than the speed of performance of individual transactions. Data is extracted periodically from the core business database and placed into a secondary database to form an organization’s information repository.
- Used for Online Analytical Processing (OLAP). This reads the historical data for the Users for business decisions.
- The Tables and joins are simple since they are de-normalized. This is done to reduce the response time for analytical queries.
- Data – Modeling techniques are used for the Data Warehouse design.
- Optimized for reading operations.
- High performance for analytical queries.
- Is usually a Database.
- It’s important to note as well that Data Warehouses could be sourced zero to many databases.