ServiceNow Certified System Administration Practice

What are the four types of table relationships?

1. one-to-one

2. one-to-many

3. many-to-many

4. none of the above

The correct answer is: one-to-many

The four types of table relationships in databases, particularly in ServiceNow, are one-to-one, one-to-many, many-to-many, and often a fourth type such as zero-to-many or self-referential, depending on context. In a one-to-one relationship, a single record in one table corresponds to a single record in another table, which is useful when you want to split data into separate tables for performance reasons or to enforce different access rights. One-to-many relationships are the most common type of relationship, where a single record in one table can relate to multiple records in another table. This relationship is fundamental in understanding how to structure data in ServiceNow and is essential for connecting records like a single user to multiple incidents. In many-to-many relationships, multiple records in one table can relate to multiple records in another table. This is often implemented by using a junction table that connects the two tables, making it possible to manage complex interactions between entities. Recognizing the existence of all these relationship types is crucial for creating an efficient data model within ServiceNow, ensuring that all data is effectively organized and accessible.