DBMS columns, column sets, and keys overview

Defines column, column set, and index key structures.


The API has three key concepts: column, column set, and index key.


A table in a database is defined by a set of columns. Each column has attributes such as a name, a type, and a maximum length (if text or binary).

A column definition is encapsulated by TDbCol .

Column set

A set of columns that describe a table are encapsulated in CDbColSet . The set can be iterated over using TDbColSetIter .

Index key

An index key orders one or more table columns (keys). It has attributes such as being unique or primary, a comparison specification for text columns, and a list of columns which make up the key.

The index key is encapsulated in CDbKey . A column for the key is encapsulated in TDbKeyCol .