We're having a discussion about using Equals
or ==
on an int comparison in a LINQ query. We're using EF4.1 Code First. What is better?
var query = context.Boodschappen
.Where(b => b.BoodschapID == id).FirstOrDefault();
or:
var query = context.Boodschappen
.Where(b => b.BoodschapID.Equals(id)).FirstOrDefault();
And why ?
For Linq To Sql, you want neither. Instead, use Object.Equals: .Where(b => Object.Equals(b.BoodschapID, id)
Why? Because of a Bug in the SQL Generator if id happens to be a nullable uniqueidentifier. If using b.BoodschapID.Equals(id) or b.BoodschapID == id and b.BoodschapID happens to be a nullable Guid, the generated SQL will not be WHERE BoodschapID IS NULL
but rather WHERE BoodschapID = @p0
which will not return any results.
I know for sure that EF used to have the same bug. No idea if it's solved yet. You can find more details in this question , just be aware that some of the answers generate horrendous SQL.
Apart from that, there is no difference between Equals and == in Linq To SQL that I'm aware of.
I 'prefer' the former. It works on nullable properties too.
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