System catalog tables
The system catalog consists of tables and views that describe the structure of the database. Sometimes called the data dictionary, these table objects contain everything that the database knows about itself. Each system catalog table contains information about specific elements in the database. Each database has its own system catalog.
These topics provide information about the structure, content, and use of the system catalog tables. It also contains information about the Information Schema, which provides information about the tables, views, and columns in all the databases of the HCL Informix® instance to which your user session is currently connected.