What is the main characteristic of a Set Table in Teradata?

In Teradata, a Set Table is specifically designed to disallow duplicate rows. This characteristic is essential in ensuring data integrity and maintaining uniqueness within the dataset. When creating a Set Table, the structure is defined in a way that enforces this rule, meaning that if an attempt is made to insert a duplicate row, the operation will fail.

Understanding the nature of Set Tables is crucial for database management because they allow users to have complete confidence that each entry is unique. This is particularly important when dealing with primary keys or unique identifiers in a dataset, where duplicates could lead to inconsistencies and erroneous analyses.

Contrastingly, a Volatile Table would allow duplicates, which is a characteristic defining its use case. While metadata is indeed important in a database context, it is not a defining feature of a Set Table. A derived or virtual table may hold different properties as well, such as being a representation of queries without storing actual data. Hence, the focus on disallowing duplicates is what establishes the primary nature of a Set Table in Teradata.