Re: Recursive Queries

Gregory Stark wrote:
> "Martijn van Oosterhout" <kleptog@svana.org> writes:
> 
>> On Thu, Jan 25, 2007 at 11:08:14AM +0000, Gregory Stark wrote:
>>> b) I do want to be able to support depth-first searching too. I'm not sure how
>>> to reconcile that with the repeated-join conceptual model. We could always
>>> resort the entire result set after generating it but that seems like an
>>> unsatisfactory solution.
>> If you have a tuplestore storing the intermediate tuples for looping,
>> then surely the only difference between depth and breadth searching is
>> that for the former new tuples goes to the front of the tuplestore, and
>> the latter to the end.
> 
> That's basically how the existing patch approached the problem. It invents a
> new type of join and a new type of tuplestore that behaves this way. This has
> the advantage of working the way Oracle users expect and being relatively
> simple conceptually. It has the disadvantage of locking us into what's
> basically a nested loop join and not reusing existing join code so it's quite
> a large patch.

I believe our Syntax should be whatever the standard dictates,
regardless of Oracle.


Joshua D. Drake



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