Assignments on attributes

Records are assigned values from attributes. An assignment indicates that a record has a value from an attribute.

A record typically has assignments from multiple attributes. For each assigned attribute, the record may have one or more values. An assignment on an attribute is known as a key-value pair (KVP).

Not all attributes will have an assignment for every record. For example, for a publisher that sells both books and magazines, the ISBNnumber attribute would be assigned for book records, but not assigned (empty) for most magazine records.

Attributes may be single-assign or multi-assign:

• A single-assign attribute is an attribute for which each record can have at most one value. For example, for a list of books, the ISBN number would be a single-assign attribute. Each book only has one ISBN number.
• A multi-assign attribute is an attribute for which a single record can have more than one value. For the same list of books, because a single book may have multiple authors, the Author attribute would be a multi-assign attribute.

At creation time, the Dgraph attribute is configured to be either single-assign or multi-assign.