How to Perform Inner Joins with LINQ to SQL?

Use Linq to SQL to execute internal connection

When dealing with SQL operations, internal connections are essential for data retrieval in optimizing the data database. Let's explore the standard syntax of internal connection in C#in C#.

Inner connection query

Assume that you have a SQL statement for internal connection operations:

select DealerContact.*
from Dealer 
inner join DealerContact on Dealer.DealerID = DealerContact.DealerID

To represent this statement as Linq to SQL, please use the following syntax:

var dealerContacts = from contact in DealerContact
                     join dealer in Dealer on contact.DealerId equals dealer.ID
                     select contact;

Here, we start with

clauses, specify the source table (dealercontact). from The clause uses equal conditions on the dealerid field to link the DealerContact table to the Dealer table. Finally, we use <子> clauses to select the required fields (dealercontact.*). join select The alternative method of specific query

But, if you clearly want to score data from the dealerContact table from the dealer, you can modify the query slightly:

This allows you to adjust the query flexibly according to the required output.

var dealers = from dealer in Dealer
              join contact in DealerContact on dealer.DealerID equals contact.DealerId
              select dealer;

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