I worked as a Salesforce admin for an organization that manages multiple projects. The organization’s multiple teams often work on several projects at the same time. However, each project may involve many teams working on it. Recently, I was required to track the activity of teams that are currently working on a specific project.
To achieve this requirement in Salesforce, we have a junction object, using which we can create many-to-many relationships between two objects.
Here, we will learn about junction objects in Salesforce, and I will explain how to create junction objects in Salesforce with examples and step-by-step explanations.
Junction Object in Salesforce
In Salesforce, we can create one-to-one or one-to-many relationships using master-detail or lookup relationships. But when we want to create many-to-many relationships between two objects, we need to create a third object called a junction object. In that junction object, we add records of the other two objects by using a foreign key that references the primary key of the other two objects.
In a many-to-many relationship, the junction object we create is always on the child’s side. That means it will be the many-sided object, which will reference the parent records of the other two objects.
When we create a junction object, we need to create a master-detail relationship between it and other parent objects. This is because when we delete the parent object’s records, the records related to that object from the junction object should also be deleted. Always remember that the junction object always has two master-detail relationship fields.
The primary and secondary relationships are automatically created when we create the junction object. In the below, I explained these relationships:
Primary Relationship: When creating a master-detail relationship between a parent object and a junction object, the field you create first will become the primary relationship field, and with which object you create, that field will become the primary master object.
Secondary Relationship: After creating a relationship with the first object, the other relationship will become the secondary relationship field, and that object will become the secondary master object.
So, the junction object with which we have a primary relationship or which is the primary master object will have all the properties of that object, such as owner name and sharing setting, applied to the junction object.
Many-to-Many Relationship using Junction Object in Salesforce
Using the following diagram, we will try to understand how to create a many-to-many relationship between two objects in Salesforce.
There are two objects: Teams and Projects. We want to create a many-to-many relationship between these two objects to assign multiple teams to multiple projects. To achieve this in another database, we need to create a different table to show the many-to-many relationship between the two tables.
However, in Salesforce, we need to create a third object called a Junction object. Only using the junction object can we create many-to-many relationships in Salesforce.
Now, in the junction object, you can see the Account team and QA team working on multiple projects. Using the junction object, we can show many-to-many relationships between two objects.
Create Junction Object in Salesforce
For example, you have two custom object teams and projects. Each team can work on multiple projects, and each project can have multiple teams. The requirement is that you need to manage teams and projects and track which teams are working on which Projects.
Here, I created two objects, Teams and Projects, which will be the parent records of the junction object, which we will create in the following steps. In these objects, I created some teams and project records.