What is LINQ and what is not LINQ? -


i've seen examples of following referred linq.

var y = _context.persons; iqueryable<person> x = _context.persons; var z = tblperson in _context.persons         select tblperson;

are linq, different flavours of or z linq? if other 2 called? if they're linq how differentiate between 3 when googling information them? y , x should using var or iqueryable in mvc core (and why) , should using either on z?

thanks jereon links. wasn't sure if var or iqueryable intrinsically linked implementation of linq or whether more generic question. generic is.

from links above variety of linq 

from tblperson in _context.persons         select tblperson;

is referred either

  • query syntax
  • query expression
  • query comprehension syntax

while variety of linq 

db.person = _context.persons                     .include(px => px.gender)                     .include(px => px.title)                     .include(px => px.addressids)                         .theninclude(px => px.addresstype) .where(px => px.name.contains("foo") .orderby(px => px.name);

is referred either

  • extension method
  • method syntax
  • fluent syntax

as usage, general opinion seemed in 2 camps

  • use 1 or other throughout project

  • mix-and-match use query syntax following

    • when using let keyword
    • when have multiple generators (from clauses)
    • when doing joins

and extension method else.


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