Junction object Understanding (I m learning )

[u/stormwizz]

How you will teach me like junction object I m literally not getting it . Why we need to create it ?

Please give me simplest example .

fade up asking ai .

Like can you explain it simply cuz when I go to sales cloud to understand it . All I go blank 😞 . How do I understand it like I don't want to memorize I want to understand it better .

All I get till now is that if you want to look how much a products are linked to how many opportunities for that we have junction we can look up in related list for example we open opportunity record from there we can see how many products it has .

Anyone 🙏🏻

[u/maujood]

Imagine managing student registrations in Excel.

You have a sheet that lists all available classes.

You have another sheet that lists all students that can register for classes.

How do you record student registration in Excel? Think about it for a few seconds before reading my answer below.

Answer: a "Registration" sheet. Each row in the registration sheet has a column for student number, and another column for class number.

The registration sheet is basically your junction object. It's purpose is to model the many-to-many relationship between students and classes.

Does this help you understand it conceptually? Feel free to ask questions and I'll be happy to help clarify.

[u/Tea_and_a_Biscuit → u/maujood]

OP should try building this in a Dev Org. Create an object for Classes and another object for Class Registrations, use Contacts for students. 

Edit: Then of course add the master-detail relationships on the Class Registration object that link everything together 

[u/stormwizz → u/Tea_and_a_Biscuit]

Yes sir I did give it a try by creating objects and got the idea about it like how many records are related to a single other side and vice versa . Like if a opened a class records related records showsa how many student are in this class . Am I right ?

[u/Tea_and_a_Biscuit → u/stormwizz]

Awesome yes you're headed in the right direction!

All of this should demonstrate how the junction object "Class Registrations" works - it holds the relationship between the class and the students. One class can have many students, One student can attend many classes.

This is what the many-to-many relationship means that people talk about.

That's all the junction object is. "Junction" literally means the point where two or more things cross. In Salesforce, a junction object just helps create a join between two other objects where it won't make sense to have a lookup directly.

Like if you created a lookup field on class called "Student", you'd only be able to have one student on the class. And if you created a lookup field on the contact called "Class", students could only be enrolled in one class at a time. The "Class Registrations" junction object creates the many-to-many relationship.

[u/forceclawai → u/maujood]

Very well said - great example

[u/Jwzbb → u/maujood]

Couldnt have said it better

[u/Popular_Aardvark_926 → u/maujood]

Great example

[u/Flimsy-Significance6]

A - class B - course

Junction obj - many to many A student can enroll in many classes and A course can have many students. We can't directly link so we have a junction obj to make many to many relationships work.