How is a one-to-one relationship symbolized in a diagram?

In a diagram, a one-to-one relationship is correctly symbolized by ending with one short mark at each end of the relationship line. This indicates that for each instance of an entity A, there is exactly one corresponding instance of entity B, and vice versa. The use of a single short mark effectively communicates that the relationship is exclusive to one-to-one pairing, ensuring clarity in relationship modeling within entity-relationship diagrams.

The other symbols mentioned represent different types of relationships. For instance, a crow's foot signifies a many relationship, indicating that an entity in the relationship can relate to multiple instances of another entity. Therefore, understanding these symbols is crucial for accurately interpreting and designing database schemas and diagrams.