Hi Chandrashekar,

You can query the junction object with the id of one of the two objects between which the junction object is created. The junction object must have a lookup on both of the objects.

Take the example below. I have a junction object between pricebook and products named PricebookEntry. I have the Id of the product and I want to find the junction object record so I'll simply query it with the help of product Id.

Like this:

public class DeleteJunction {
    public static void deletejunc(){
        List<PricebookEntry> pbentryList = [SELECT Id, Product2Id, Pricebook2Id WHERE Product2Id = "012nsx92scsd1xx001"];
        
        delete pbentryList;
    }
}

I hope you find the above solution helpful. If it does, please mark as Best Answer to help others too.

Thanks and Regards,
Deepali Kulshrestha
www.kdeepali.com

Hi Chandrashekar,

-> Every junction object is created between two sObjects or two Custom Objects.
-> Junction objects are used to create many to many relationships between objects
-> Junction Object contains ids of both objects that it is created for.

Let's take an example, In salesforce there are two sObjects (Pricebook and Product) and they contain a junction object named as PricebookEntry
you can also see the relationship between objects using the below link:

https://salesforce.stackexchange.com/questions/215991/salesforce-data-design-tool

* First we need to make a Product because its ID id required in the creation of PricebookEntry
 
        Product2 p = New Product2();
        p.Name = 'hello';
        p.IsActive = True;
        insert p;
   
* Now we need to create Pricebook because its ID id required in the creation of PricebookEntry
  
        PriceBook2 pb = new PriceBook2();
        pb.Name = 'Algo12';
        pb.IsActive = true;
        insert pb;
        
*  Now its time to create PriceBookEntry

        PriceBookEntry pbe = New PriceBookEntry();
        pbe.Product2Id = p.Id;                       //parentID
        pbe.Pricebook2Id = pb.id;                    //ParentID
        pbe.IsActive = True;
        pbe.UnitPrice = 100;
        insert pbe;

-> If you want to delete any ParentID then your junction object is also going to delete since the child record (PriceBookEntry) does not have any parent.
-> And if you delete any juction object record then both its parent isn't going to delete.
-> For deleting a record you just need to get that record from database by querying it in apex code and simply write: 

      delete pbe;                                    // for above example

I hope you find the above solution helpful. If it does, please mark as Best Answer to help others too.

Thanks and Regards,
Ajay Dubedi
www.ajaydubedi.com