LDB_SCOPE_ONELEVEL without full traversal?

[tridge at samba.org]

Simo,

 > I think that, while the parentDN hack will certainly work, we should
 > think of implementing it internally as one level searches are not so
 > rare.

I disagree :-)

Can you tell me when a windows client does a one level search that
needs to be fast? Have you measured how fast it currently is?

 > It will not really be an upgrade problem, all I have to do is to add a
 > special index so that newer versions will just create this index if it
 > is not found.

every additional index you add is one more write you need to do on
every database modification.

One of the reasons ldb is so much faster than other ldap servers for
the loads we have is that we don't do these sorts of performance
enhancements for the less common cases. So we don't have prefix or
suffix indexes, we don't have onelevel indexes etc.

 > I will try to work on this in the weekend.

please first prove that it won't cost us more than a fraction of a %
of performance. 

By making this (rare!) onelevel case fast, I think you will
significantly impact the performance of much more common operations.

Tree traversals tend to be done by GUIs, and GUIs operate at human UI
speed, which is _slow_. Expression searches are used by non-GUIs and
those operate at protocol speeds, which is _fast_.

Cheers, Tridge