An inner join is the most common join operation between entities and represents the default join-type. The query compares each row of entity A with each row of entity B to find all pairs of rows that have an association and satisfy the join-predicate. If the association exists and the join-predicate is satisfied, column values for each matched pair of rows of A and B are combined into a result row.
The syntax is as following:
[ INNER ] JOIN entity_path [ ON <constraint> ]
entity_path Specifies the entity to join and the path from an earlier defined entity in the FROM clause to this entity. The path Crm.Customer/Crm.Customer_Address/Crm.Address defines a path from the earlier defined entity Crm.Customer to the new entity Crm.Address.
Constrains the specified entity in the JOIN part of the FROM clause. The constraint syntax is similar to that in the WHERE clause. Only the entities and from-aliases from the current and preceding JOIN elements can be used in the constraint.