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Linq: Query for multiple join conditions in Linq to SQL

This is common to join a table with another on multiple conditions, Like

Select * from Customer c
Join Invoice i on c.CustomerID = i.CustomerID and c.CustomerTypeID = i.CustomerTypeID

I need to write a Linq to SQL query for the same scenario. But the syntax for this query is a bit different to expect. The Linq query is as follows:

From c in DataContext.Customers
Join i in DataContext.Invoices on new { c.CustomerID, c.CustomerTypeID } equals new { i.CustomerID, i.CustomerTypeID }

*DataContext in the above query should be replaced with actual datacontext name.
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Comments

  1. Arun KumarJanuary 23, 2011 at 2:15 AM

    Hi Thanks for the tip. I am actually for something dynamic joins where the no. of columns may vary for each execution and hence the conditions.
    Can u please come up with some syntax that solve the purpose.

    --Arun
    Please do mail me once you got the solution on mail.arun2005@gmail.com

    ReplyDelete
  2. UnknownAugust 5, 2018 at 9:02 PM

    what would be the LINQ syntax for :- Select * from Customer c
    Join Invoice i on c.CustomerID = i.CustomerID OR c.CustomerTypeID = i.CustomerTypeID

    ReplyDelete
  3. MrinsAugust 30, 2018 at 12:46 AM

    This code will not work, Anonymous types in linq join needs field name, even better to use a class with IEquatable

    ReplyDelete

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