What is a data dictionary?
Many people seem to be aware of the fact that data dictionaries are important for their company, but can’t say exactly what they are or why they’re important. Data dictionaries play a crucial role in ensuring a company’s data management system—e.g., CRM—is accurate and reliable. An important concept to understand when discussing data dictionaries is that they do not hold any actual data, but information about the data.
Data dictionaries store what we call “metadata,” information about how to store and manage the data in a database system. Having a data dictionary allows the database administrator to know the type of field, where the field is located, and what each field means. Having this information easily accessible can contribute significantly to your company’s data accuracy.
In order to better understand data dictionaries, we must know exactly what information they hold.
A data dictionary often contains the following information about fields:
- Default values
- Constraint information
- Definitions (e.g., functions, sequence)
- The amount of space allocated for the object/field
- Auditing information
A data dictionary is often used as a “read-only” reference in order to obtain information about a database. The dictionary acts as a way to describe data in “real-world” terms. This significantly contributes to the organization of a database. Without a data dictionary, a database could easily be chaos. The organization of a database is important for maintaining information reliability.
As we all know, the accuracy, reliability and organization of a database can greatly contribute to the overall success of a company. Data dictionaries play a central role in maintaining this integrity.