The Difference between Master-detail and Lookup Relationships in Salesforce: A Detailed Comparison

In the Salesforce data model, data is organized using three major building blocks – Objects, Fields, and Records. Objects are similar to tables in a database, whereas fields represent columns and records represent rows.

To organize Salesforce data, enable efficient data access, and ensure data consistency, data relationships come in handy. A data relationship in Salesforce refers to the way objects (tables containing data) are connected to each other. In other words, data relationships define the way how records in one object are connected to records in another object. 

Master-detail and lookup relationships are the two most common types of data relationships used in Salesforce. The major difference between them is – 

• The master-detail relationship is tightly coupled. If you delete the parent, all child records get deleted. This implies the child object cannot exist without the parent object.
• The lookup relationship is loosely coupled, wherein the child object can exist without the parent.  

In this blog, we shall delve into the details of master-detail and lookup relationships, their benefits, and examples. Also, we shall have a detailed comparison of master-detail vs lookup relationships.

What is a Master-Detail Relationship? 

A master-detail relationship in Salesforce refers to a tight integration between two Salesforce objects. In this relationship, one object acts as a parent (master) and the other object acts as a child (detail).

The child object inherits all the security settings from the parent object. For instance, if you have the privilege of viewing, editing, or deleting data in the parent object, the same access rights extend to data in the child object. 

Key Features

Here are the characteristics of the master-detail relationship in Salesforce: 

• Parent-Child Dependency: The child object is entirely dependent on the parent object. It cannot exist autonomously. If you delete the parent, all the related child records get deleted, which is referred to as cascade delete. 
• Ownership: The parent object owns the child object. Child records inherit all the parent’s security settings. 
• Rollup Summary Fields: You can create rollup summary fields on the parent object, which aggregates data from the related child records. It supports 4 different aggregate functions – Count, Sum, Max, and Min. 

Example of Master-Detail Relationship in Salesforce 

Imagine that you operate an e-commerce store and utilize Salesforce to manage orders, sales, inventory, customer relationships, and more. 

To understand the master-detail relationship, let us take into account order management. A single order can contain multiple products (order line items). So, in the master-detail relationship –

• Parent object: Order
• Child object: Order Line Items 

Explanation: 

• Each Order Line Item is tightly associated with the Order. If an order contains 3 products, three Order Line Items will be linked to that Order. 
• If you delete the parent object, Order, all the related child records, Order Line Items, will be deleted. 
• When you create a rollup summary field on Order, you can calculate the total number of Order Line Items using COUNT or the total amount for all items using SUM. 

Benefits of Master-Detail Relationships in Salesforce

• Data Integrity: Strong dependency of a child object on a parent ensures that child records are always bound to parent records. When you delete the parent object, the child object automatically gets deleted, leaving no orphaned records. This ensures data integrity and consistency. 
• Easy Data Aggregation: By creating rollup summary fields on the parent, you can quickly summarize key metrics like the total value, count of records, the highest value among the child records, etc., for child records. 
• Consistent Security: The access control for the parent and child records stays the same due to their strong dependency. This simplifies security management and reduces the risk of unauthorized access. 
• Efficient Data Management: Due to the cascading behavior, managing child records becomes easier when you delete or update parent records. 

What is a Lookup Relationship? 

A lookup relationship in Salesforce represents a more loosely coupled connection between Salesforce objects. In this relationship, a child object is less independent of a parent. As a result, it is not necessary for the child object to have a parent by default. While it can reference the parent object, the child object has the flexibility to exist without the parent. 

Key Features 

The following are the salient features of lookup relationships in Salesforce:

• Optional Dependency: The child object does not completely depend on the parent. So, when you delete the parent, the child records will not be deleted automatically; only the field referencing the parent will be blank. The child records will not be deleted until you configure them explicitly. 
• No Ownership: Child records have independent security settings. They do not inherit the parent’s security settings. 
• No Rollup Summary Fields: In Salesforce, you cannot create rollup summary fields on objects with lookup relationships. You must use third-party tools like RollUp Magic to enable the creation of rollup summary fields on lookup relationships. 

Example of Lookup Relationship in Salesforce 

Let’s take the scenario we discussed in the master-detail relationship example. 

For every order, you create an invoice to collect the payment from the buyer. Let us say that you want each order line item to reference a specific product. In this case, a lookup relationship comes in handy. 

• Parent object: Represents a catalog of products for sale. 
• Child object: Represents Object Line Items, which are specific products in an order. 

Now consider that a customer places an order with two items – “computer” & “mouse”, which are Order Line Items. In a lookup relationship, these items will reference the corresponding products (Laptop, Mouse) in the product catalog.

Benefits of Lookup Relationships in Salesforce 

• Preservation of Data: When you delete the parent object in a lookup relationship, associated records in the child object are not automatically deleted. This ensures that associated child records remain intact even if you delete the parent. 
• Easy Record Creation: You can easily create child records in the Salesforce lookup relationship, as it is not mandatory to have the parent record. This results in greater flexibility and autonomy. 
• Multiple Lookups: Salesforce allows a maximum of 25 lookups for a single object. This flexibility enables you to associate a single record with multiple other records without the constraint of the parent-child hierarchy.   
• Flexibility in Implementation: You can establish connections between objects even if the child objects hold no records. 

Master-Detail vs Lookup Relationships in Salesforce: A Head-to-Head Comparison

Let’s now dive deeper into the differences between master-detail and lookup relationships in Salesforce. 

RollUp Magic: A No-Code Solution to Create Rollup Summary Fields on Objects with Lookup Relationships

As we already discussed, the lookup relationship does not support the creation of rollup summaries in Salesforce. RollUp Magic is a no-code solution that lets you create rollup summaries for objects with lookup relationships.

Developed by Ksolves India Limited, RollUp Magic is a no-code solution designed to streamline data management and reporting in Salesforce. With its graphical user interface, you can create rollups with just a few clicks. It supports 5 different aggregate functions – SUM, COUNT, MIN, MAX, and AVG.

What’s more interesting is the tool lets you create rollup summary fields on custom objects in addition to standard objects in Salesforce.

Let’s have a look at some noteworthy features of RollUp Magic. 

Conclusion 

This was all about the difference between master-detail and lookup relationships in Salesforce. While the master-detail relationship presents a tight connection between objects, the lookup relationship corresponds to a loosely coupled association. Both these relationships have different behaviors, functionalities, and the impact on data management in Salesforce.

With strong dependency between parent and child objects, master-detail relationships ensure data integrity, robustness, and streamlined security. On the contrary, the lookup relationship in Salesforce offers flexibility as child records are independent of the parent.

The major drawback of the lookup relationship is it does not support rollup summary fields. However, RollUp Magic is a UI-based tool that enables the creation of rollup summary fields on objects with the lookup relationship. Give it a try and elevate your Salesforce data management and reporting capabilities.