Data warehousing tools included in a standard software package can be divided into four primary categories: data extraction, table management, query management, and data integrity. A data warehouse is a repository for large sets of transactional data, which can vary widely, depending on the discipline and the focus of the organization. For example, many scientific research projects collect huge amounts of data for analysis and review. A data warehouse may be the best technology to manage and store this information.
It is important to note that specific skill sets are required for all staff who work with data warehousing tools. This type of technology requires training in statistics, advanced math, processing logic, relational databases, and advanced computer skills. Many people in this field began their careers in statistics or computer science. The concepts used to create and manage the data flow are quite complex and require significant time and effort to master.
A data warehouse requires a method of adding data to it, and an extraction, transform, and load (ETL) tool is typically used for this purpose. The tool itself is a software program used to correctly identify the appropriate information from another computer system, based on the user's criteria. This data may need to be normalized or modified for consistency or to match the warehouse database structure. Loading the data is critical, as all the relationships and connections to other databases must be maintained to ensure the integrity of the database, so it can be used with other tools.
Every data warehouse contains a vast number of database tables that are organized to work with each other in a logical, systematic way. The maintenance of these tables is essential to the continuing operation and accuracy of the data warehouse. Using the concept of relational databases, they must be maintained and validated on a regular basis because any faults or failures will result in inaccurate reporting.
A query is simply a programmed question or report request, and there is an entire business process surrounding the creation of a data warehouse query. This process requires in-depth knowledge and understanding of the business needs, as well as the data structures within the data warehouse. Business intelligence specialists are trained professionals who have the combination of skills and training necessary to create and manage multiple, customized queries.
A data integrity function is standard in most warehousing tools. These modules are often extremely complex to use, with multiple options and functions available, but they are absolutely essential to the creation and maintenance of a functioning, useful data warehouse. Data integrity tools check for consistency within the data, accurate connections between databases, and clean programming logic. Poor data integrity will result in a data warehouse that provides inaccurate reports, resulting is poor business decisions.