Metadata

Abstract

As a professional developer, you probably spend a portion of your time building database applications that allow users to both enter and retrieve some kind of data. Data makes up the content of a given database and is generally what’s most important to the users of a database system. This person needs a data acquisition program, and that person wants a business intelligence reporting application. With all the focus on data, why should anyone care too much about metadata? For starters, metadata is data about data. Without it, you’d have an awfully hard time figuring out where to put data and how to get it back out. Metadata describes things like column names, data types, indexes, and most other database objects and structures. As you might imagine, creating database queries would be impossible without prior knowledge of database metadata. You’ve actually spent a lot of time working with metadata during the last two chapters. When you created tables and columns visually with Query Analyzer or with Data Definition Language code, you were creating database metadata. While Query Analyzer made it easy to view that metadata, I’m sure you’d like the option of discovering and viewing this information programmatically.