While taming the subject of indexes, we recently had some discussion with one of our users who complained about long response times with some language specific search filter such as (cn:fr.6:=*John*).
These extended filters rely on I18N Collation matching rules and indexes that I’ve described in an old post for OpenDS.
It turned out that he had defined the matching rule for the index, and rebuilt it, but had missed an important part: the index-type did not include “extensible”.
The proper command to create an extensible index is the following :
dsconfig set-local-db-index-prop --backend-name userRoot --index-name cn \ --set index-extensible-matching-rule:fr.6 \ --add index-type:extensible \ --hostname localhost --port 4444 \ --bindDN cn=Directory\ Manager --bindPassword ****** \ -X -n
fr.6 is the shortcut for the French substring collation matching rule which full OID is 1.3.6.1.4.1.42.2.27.9.4.76.1.
Note that if you don’t specify the extensible index-type, the server will not build the index for the extensible matching rule. The use of the index-type is consistent with the other types of index, equality or else, and allows you to disable and re-enable extensible indexes without having to re-enter all OIDs.
Pavel Heimlich, also known as Hajma on in the 
Ludo Sketches 