Standard report types by relationship type
Key Takeaway
The relationship you build decides what a standard report type can join: two objects for a lookup, three for a master-detail, and both masters plus the junction object for a many-to-many.
A report type sets which records and fields a report can use, based on how a primary object relates to its related objects. Salesforce provides standard report types for objects. The kind of relationship you build affects which standard report types are available and how they are categorized. Those report types decide which related objects a report can include.
What each relationship type gives you
| Relationship type | What you get |
|---|---|
| Lookup | A standard report type that joins data from the two related objects in one report |
| Master-detail | A standard report type that can join three objects: the master, the detail, and one other object that the detail looks up to |
| Many-to-many, through a junction object | Two standard report types that join both master objects and the junction object |