What is the relationship between opportunity line item and PriceBook in Salesforce?

Hello Anjali,

Here is the relationship between Opportunity,OpportulityLineItem ,PricebookEntry,Pricebook and Product2 .

1. OpportunitylineItem is junction object between opportunity and pricebookentry.
As We need PricebookEntry Id and opportunity Id while creating OpportunityLineItems.

2. PricebookEntry is a junction object between Product2 and PriceBook.
As we need Product2 Id and PriceBook2 Id while creating PricebookEntries.

Whenever we add products on any opportunity ,behind the curtain this data model works.

Thanks.