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Re: LANGUAGE/COMPARATOR review




Hi Ken,

--On November 16, 2006 9:56:29 AM -0500 Ken Murchison <murch@xxxxxxxxxxxxxx> wrote:

So, SORT/THREAD use a minimum of two collations, and upto three in the
case of ORDEREDSUBJECT. The question is whether these will ever need to
be specified separately. I think it may be prudent to at least define
two COMPARATORs, not one. One would be the active collation for
comparisons, the other the active collation for ordering operations.

I can see arguments for using one collation throughout, or having two
separate collations.  I don't have a string opinion either way.

Cyrus, do you have a suggestion for how a second comparator would be
selected?  Would this be an addition to COMPARATOR or an addition to
SORT/THREAD?


Well, are there other places where we might do sorting? One possibility might have been LIST-EXTENDED, but as we know LIST responses are not ordered. I know at some point there had been discussion of a sort order preserving COPY operation.

If we want to have separate collations for these steps then I think adding a parameter to SORT/THREAD would be better. Note that METADATA is going to do that for the METADATA select option in LIST-EXTENDED. However, there needs to be a convincing argument for this.

All I can come up with is: I might want SEARCH on Priority using i;ascii-numeric as the active collation, but that would be inappropriate for the ordering or grouping operations in either SORT or THREAD.

--
Cyrus Daboo