Re: New patch for Column-level privileges - Mailing list pgsql-hackers

From Stephen Frost
Subject Re: New patch for Column-level privileges
Date
Msg-id 20090107141630.GO26233@tamriel.snowman.net
Whole thread Raw
In response to Re: New patch for Column-level privileges  (KaiGai Kohei <kaigai@ak.jp.nec.com>)
Responses Re: New patch for Column-level privileges  (KaiGai Kohei <kaigai@ak.jp.nec.com>)
List pgsql-hackers
KaiGai,

* KaiGai Kohei (kaigai@ak.jp.nec.com) wrote:
>> Is it possible to implement a walker function to pick up appeared
>> columns and to chain them on rte->cols_sel/cols_mod?
>> In this idea, columns in Query->targetList should be chained on
>> rte->cols_mod, and others should be chained on rte->cols_sel.

This sounds like a reasonable approach to me, but as I mentioned before,
I'm not very familiar with the analyzer and company.

> The attached patch is a proof of the concept.

Excellent, I'll play around with it.

> Any comment?

I'm generally not a huge fan of recursion simply because it's often
overrated and overused and implements a limit based on stack depth which
can cause unexpected failures.  Can we be confident that the recursion
added here doesn't add a new limit on the size/complexity of queries
which, if hit, will cause a stack overflow?  I notice that we do use
recursion in some other places, but we also occationally have checks to
prevent recursing too far.

> I strongly want the Column-level privileges to be get merged
> as soon as possible, so I don't spare any possible assist
> for his works.

Thanks so much for your help!  It's definitely appriciated.  I'm going
to try and play with your patch today and probably add some additional
regression tests and make sure everything works as expected.
Thanks again!
    Stephen

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