Re: [HACKERS] what standard say ...

Thomas G. Lockhart wrote:
> 
> > vac=> select count(*) from test where exists (select t1.y from test t1 where t1.y = x);
> >                                                                                     ^
> > Is this correlated subquery or not ?
> > (Note, that I don't use x with t1. prefix here)
> > With current parser this works as un-correlated subquery...
> 
> >From "The SQL Standard", 3rd ed., Date and Darwen:
> 
> "... each unqualified column name is _implicitly_ qualified by a range variable name
> defined (explicitly or implicitly) in the nearest applicable FROM clause." (the emphasis
> is from the book, not me)
> 
> It goes on to recommend reading the standard for full understanding, but it is pretty
> clear that your interpretation is correct; in the example above x is implicitly equivalent
> to t1.x.

Ok. Nice to know that we are correct here :)

Vadim