Language Integrated Query — Where, Select, GroupBy, and deferred execution for collections and databases.
Five passes over the same idea, each from a different angle. Do them in order, or jump to whichever you need.
LINQ provides a unified query syntax for collections, databases, XML, and more. Key concepts: method syntax vs query syntax, deferred execution, IEnumerable vs IQueryable, common operators (Where, Select, GroupBy, OrderBy, Join), and performance considerations. LINQ to Entities translates to SQL via EF Core.
