select/2 explaination

select_2_explain.ex

from(c in City, select: c) # returns the schema as a struct
from(c in City, select: {c.name, c.population}) # returns Tuple of {name, population}
from(c in City, select: [c.name, c.county]) # returns List of [name, county] 
from(c in City, select: %{n: c.name, answer: 42}) # returns Map with keys :n, and :answer
from(c in City, select: %{c | alternative_name: c.name}) # returns the schema as a Struct with :alternative_name added
from(c in City, select: %Data{name: c.name}) # returns the selected name in %Data{}