Linq 'into' keyword confusion

Question

I was looking at a co-workers Linq query, shown below (the query executes correctly):

from ea in EquipmentApplication
join erl in EquipmentRoutingLocation on         


        

Answer 1

"into" has two different meanings:

• In a join clause, it changes the translation from using Join to GroupJoin. This means that instead of getting one result per matching pair, you get one result for each element of the original sequence, and that result contains the key and all the results from the other sequence, as a group. See Enumerable.GroupJoin for more details
• In a select or group...by it becomes a query continuation, effectively starting a new query with the results of the old one in a new range variable.