D3 Indices

Hi
Recent discussions about indexing set me to thinking that I should once
again look at D3 Indices. So I did a simple test. The Invoices file
contains multi-valued attributes for the invoice lines. One line is the key
to the product file. We frequently wish to sort invoice sales by Product
Group and Product name, both of which are in the Product file. I prefer F
correlatives but popped in an "A" type for the exercise. The result is fine
for LIST and SORT BY-EXP. However any attempt to create an index results in
a crash. I originally posed this question when Pick first did b-trees and
got a silly answer that did not address the question. Now that people have
had years of practise can someone explain exactly what the problem is here
( no theories please just an answer to the exact question) In my opinion
any b-tree that cannot deal with builds like this is simply a waste of
space.

:CT DICT INVOICES GRPDESC

GRPDESC
001 S
002 0
003 Product Description
004
005
006
007
008 A13(TPRODUCTS;X;3;3]MR%3):13(TPRODUCTS;X;2;2)
009 L
010 32

LIST INVOICES GRPDESC



INVOICES Product Description.............

1*514336 050Longhaul Premium
052Brake & Clutch Fluid
1*514337 052Revtex Super 2T
1*514338 050Longhaul Premium
1*514339 056Antibloat Oil
1*514340 056Antibloat Oil
056Antibloat Oil
1*514341 052Revtex Super 2T
056Antibloat Oil
1*514342 052Revtex Super 2T
056Antibloat Oil
1*514343 052Revtex Super 2T
1*514344 001Lead Replacement Petrol
1*514345 001Lead Replacement Petrol
001Lead Replacement Petrol
1*514348 095STARCARD CARD CHARGE
1*514349 095STARCARD CARD CHARGE
1*514350 095STARCARD CARD CHARGE
1*514351 095STARCARD CARD CHARGE
1*514352 095STARCARD CARD CHARGE
1*514354 095STARCARD CARD CHARGE

SORT INVOICES BY-EXP GRPDESC GRPDESC

INVOICES Product Description.............

1*516787 002Unleaded Unmarked
1*516788 009Gas
1*514336 050Longhaul Premium
1*514338 050Longhaul Premium
1*514336 052Brake & Clutch Fluid
1*514337 052Revtex Super 2T
1*514341 052Revtex Super 2T
1*514342 052Revtex Super 2T
1*514343 052Revtex Super 2T
1*514339 056Antibloat Oil
1*514340 056Antibloat Oil
1*514340 056Antibloat Oil
1*514341 056Antibloat Oil
1*514342 056Antibloat Oil
1*515159 058Block Grease 6
1*515164 058Crater 1
1*515175 058Crater 1
1*515165 058RPM Grease SRI-2
1*515178 058RPM Grease SRI-2Q

:CREATE-INDEX INVOICES GRPDESC
Creating index on A13(TPRODUCTS;X;3;3]MR%3):13(TPRODUCTS;X;2;2)
0002457
[3] The verb 'MR%3):13(TPRODUCTS;X;2;2)' is not defined.
:
There are 2457 invoices in the test file with in excess of 4,500 lines so it
appears to have indexed on attribute 13 in full which would be pretty silly
as it is multi-valued.

Peter McMurray


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