Which option is an example of an atomic value?

• A. A list of multi-valued items such as colors Red, Blue
• B. A single value such as 42
• C. A multivalued attribute stored as Red;Blue
• D. A list of colors separated by commas: Red, Green, Blue

Answer: (B)

Atomic value means a value that cannot be broken into smaller meaningful parts for that attribute. A single value such as 42 is atomic because it represents one discrete data item and isn’t a collection of separate values. The other options all convey multiple values for the same attribute: a list of colors is a collection of items; storing two values like Red and Blue in one field is a multivalued attribute; and a comma-separated string like Red, Green, Blue encodes several values in a single field. Keeping atomic values is important in data modeling because it keeps each attribute representing one thing, which simplifies querying and normalization.