AMany-to-Many (M2M) relationshipin ServiceNow allows two or more tables to be relatedbi-directionally, so that related records are visible in arelated liston both tables.
Unlike aOne-to-Many (1:M)relationship (where only one table references another), M2M relationshipslink records in both directions.
This is achieved through anintermediary table, known as aMany-to-Many table, which stores the relationships.
A Many-to-Many table contains:
Areference fieldfor each of the tables being linked.
The relationship records, which connect records between the two tables.
Suppose you want to relateIncidentstoProblemsand vice versa.
Instead of adding a reference field in each table, you create anm2m_incident_problemtable.
Now, an Incident can be linked tomultipleProblems, and each Problem can be linked tomultipleIncidents.
These relationships will be visible asrelated listsin both tables.
How Many-to-Many Relationships Work in ServiceNow:Example of a Many-to-Many Relationship:
Incorrect Answer Choices Explanation:A. Database View– Used tocombine data from multiple tablesfor reporting but does not establish abi-directional relationshipbetween tables.
C. One to Many (1:M)– Asinglerecord in one table relates tomultiplerecords in another, but the relationship isnot bi-directional.
D. Extended– Refers totable inheritance, where a table inherits fields from its parent table, not a Many-to-Many relationship.
Many-to-Many Relationships in ServiceNow
Understanding Table Relationships
Official CSA Documentation Reference: