The data companies analyze through business intelligence comes from a diverse type of data sources. The most common of these are:
- Flat files
- Web services
- Other sources such as RSS feeds
Databases are the most traditional kind of data source in BI. There are many different kinds of databases, and many vendors providing databases with different architectures and different features. Common databases used today include MS Access, Oracle, DB2, Informix, SQL, MySQL, Amazon SimpleDB and a host of others.
Traditionally, transactional databases—namely the ones that record the company’s daily transactions, such as CRM, HRM and ERP—are not considered optimal for business intelligence. This is for a variety of reasons, including the fact that a) data is not optimized for reporting and analysis and b) querying directly against these databases may slow down the system and prevent the databases from recording transactions in real time.
In some cases, companies use an ETL tool to collect data from their transactional databases, transform them to be optimized for BI and load them into a data warehouse or other data mart. The main downside of this approach is that a data warehouse is a complex and expensive architecture, which is why many other companies opt to report directly against their transactional databases.
Few companies today have not used Microsoft Excel spreadsheets. Their ease of use and widespread employ makes them as popular as ever.