ValueSelectElement

Returns a string representation of the object.

The default representation is platform dependent.

strictly for logging purposes, i.e. to display a more explicit AST

Update, Insert, and Delete statements are always at the root of an AST, so they are never aliased, but then can have sub queries, ex.: update ... where x in (subquery). Name clashes are impossible since SelectElements of query are always aliased.

visitor's args are : -the visited node, -it's parent -it's depth

In the following select :

 select t.x from t

t.x is a select element and t is it's origin

Here q.z1 is a SelectElement who's origin is t

 select q.z1
 from
   (select t.x as z1 from t) q