Indexing or sorting ordered arrays.

[Ed Kleban]

On 11/20/05 1:39 AM, "Ruslan Zasukhin" <sunshine at public.kherson.ua> wrote:

> On 11/20/05 9:31 AM, "Ed Kleban" <Ed at Kleban.com> wrote:
> 
>> When you set the fIndexed EVFlag, then V2 builds an index, correct?
>  
>> 
>> 5) I'm totally clueless because you're simply not indexing or sorting in any
>> of these ways.
> 
> Actually nature of DBMS indexing is sort of inserts.

Doh!  Of course.  It's incremental to deal with a single record add at a
time.  Makes perfect sense for adding individual records.  So then
re-indexing an already or mostly sorted array would be very fast.  Yep, yep.

But that also suggests that if I'm going to supply a very large array of
randomly ordered elements and then ebabke the "Unique" or "Indexed" flag,
that I might be better off presorting them first myself, since an insertion
sort in that circumstance could take much longer... that is if I happened to
have a plugin or RB-written sort routine that could compete with the speed
of your C++ compiled insertion sort.  True?
 
Doesn't much matter.  Most of the arrays I'm concerned with right now all
happen to be pre-sorted.

Thanks!


> For some cases of small sets we use just quicksort, but not recursive