Re: Re: GIST question

> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > I will keep the patch for a day and apply it if no one objects.
>
> I object.  You still have no idea what that test is for or whether
> there may be any value in keeping it.  It seems clear that the original
> GIST authors thought the flag was useful.
>
> I should also point out that the fact that the flag is always "true"
> today is because I ripped out some code in index.c a version or three
> back.  6.5 had
>
>     indexForm->indhaskeytype = 0;
>     while (attributeList != NIL)
>     {
>         IndexKey = (IndexElem *) lfirst(attributeList);
>         if (IndexKey->typename != NULL)
>         {
>             indexForm->indhaskeytype = 1;
>             break;
>         }
>         attributeList = lnext(attributeList);
>     }
>
> which I removed because it was a security hole (you could tell the
> system to treat any data type as any other datatype, with obvious
> possibilities for coredump).  But I didn't look hard at what the
> GIST code was using the flag for...

I did look at the code inside the tests.  The first was to decide if it
was suppose to look in pg_attribute for the byvalue flag.  The last two
controlled the if gistentryinit() was called.  No idea what that is
because the variable names are single letters.  Gistentryinit() is:

#define gistentryinit(e, pr, r, pg, o, b, l)\
  do {(e).pred = pr; (e).rel = r; (e).page = pg; (e).offset = o; (e).bytes = b;
 (e).leafkey = l;} while (0)

I have to say I have no idea how pg_index.indhaskeytype is related to
gistentryinit().

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