Subject RE: [firebird-support] Re: ORDER BY on large VARCHAR columns
Author Rick DeBay
Create a field that contains the first N characters and have the
database sort by that.
Then do an application sort, using an algorithm that works well on
nearly sorted result sets.

Create a N fields, breaking it up between them and order by n,n-1, etc.

Beg the FB gods to allow unlimited size indexes.

-----Original Message-----
From: robert_difalco [mailto:rdifalco@...]
Sent: Tuesday, October 26, 2004 9:57 PM
To: firebird-support@yahoogroups.com
Subject: [firebird-support] Re: ORDER BY on large VARCHAR columns



--- In firebird-support@yahoogroups.com, Helen Borrie <helebor@t...>
> >has qualified names much like a file system, but they cannot be
> >chopped up and stored hierarchically.
>
> Why is that so?

Because they would just have to be re-concatenated into a qualified
name and displayed sorted again. I'm pretty sure that would take
even longer. Also, there is a table that joins with each qualified
name.

So there are no tricks of the trade, nothing to do to improve the
sort speed of a large VARCHAR column? Seems like I am pretty
consistently hearing "Doctor it hurts when I do that" -- "Don't do
that". ;) I sure wish I could just create an index on it, regardless
of the size.







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