LINQ to SQL with multiple tables and multiple column join

I have three datatables


dt1 has three columns ID, Date, Price
dt2 has two columns ID, CurrencyCode,
dt3 has three columns CurrencyCode , Date , Rate

I need to join the three tables

                                                      from dataRows1 in dt1.AsEnumerable()
                                     join dataRows2 in dt2.AsEnumerable()
                                     on dataRows1["ID"] equals dataRows2["ID"]                                
                                     join dataRows3 in dt3.AsEnumerable()
                                                       on dataRows2["CurrencyCode"]  equals dataRows3["CurrencyCode"] AND dataRows1["Date"] equals dataRows1["Date"]
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käµfm³d 👽Commented:
The last bit of your query needs to introduce anonymous objects. You do this any time you need a mult-column join. For example:

join dataRows3 in dt3.AsEnumerable() on
new { CurrencyCode = dataRows2["CurrencyCode"], Date = dataRows1["Date"] } equals
new { CurrencyCode = dataRows3["CurrencyCode"], Date = dataRows3["Date"] }

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