Question

I have a table was named “MYTABLE”. That have two columns “FIRSTNAME” and “LASTNAME”.
Two query below returned same result is IQueryable<MYTABLE>

dataContext.MYTABLEs.Where(f => f.FIRSTNAME == firstName && f.LASTNAME == lastName);

from t in dataContext.MYTABLEs
where t.FIRSTNAME == firstName && t.LASTNAME == lastName select t;

What is the difference? which one in the two query faster?

Answer 1

They’re both the same. You can write LINQ queries using lambda (method) syntax (the 1st approach) or query syntax (the 2nd approach). The latter is simply syntactic sugar and both get compiled to the same thing.

From the LINQ Query Syntax versus Method Syntax MSDN article:

there is no semantic difference
between method syntax and query
syntax. In addition, some queries,
such as those that retrieve the number
of elements that match a specified
condition, or that retrieve the
element that has the maximum value in
a source sequence, can only be
expressed as method calls.

A similar question can be found here.