[Monetdb-developers] Will optimisations occur in storage when indexing is applied?
Hi, If a user places an index on a varchar column will the actual character storage move to an intermediate (or final) column with only unique instances of each string. Or will the storage in the original table definition still contain all materialized string, instead of pointers to the index? Stefan
Hi,
If a user places an index on a varchar column will the actual character storage move to an intermediate (or final) column with only unique instances of each string. Or will the storage in the original table definition still contain all materialized string, instead of pointers to the index? There are 2 indices in monetdb. The prime purpose are to speed up
On Fri, Aug 22, 2008 at 03:42:40AM +0200, Stefan de Konink wrote: primary and foreign key checks. Both only store numbers (hash values and oid's for the primary-foreing key relation). So we cannot reduce the varchar storage in this case. However the primary storage of varchar's does allready do this duplicate elimination and only stores pointers too strings. Niels
Stefan
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-- Niels Nes, Centre for Mathematics and Computer Science (CWI) Kruislaan 413, 1098 SJ Amsterdam, The Netherlands room C0.02, phone ++31 20 592-4098, fax ++31 20 592-4312 url: http://www.cwi.nl/~niels e-mail: Niels.Nes@cwi.nl
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Niels Nes -
Stefan de Konink