Red Hat Directory Server 8.0 Administrator's Guide

System indexes cannot be deleted or modified. They are required by the directory to function
properly. Table 10.2, “System Indexes” lists the system indexes included with the directory.
Attribute Eq Pres Purpose
aci Allows the Directory
Server to quickly
obtain the access
control information
maintained in the
database.
objectClass Used to help
accelerate subtree
searches in the
directory.
entryDN Speeds up entry
retrieval based on DN
searches.
parentID Enhances directory
performance during
one-level searches.
numSubordinates Used by the Directory
Server Console to
enhance display
performance on the
Directory tab.
nsUniqueID Used to search for
specific entries.
Table 10.2. System Indexes
1.2.3. Overview of Standard Indexes
Because of the need to maintain default indexes and other internal indexing mechanisms, the
Directory Server also maintains certain standard index files. The standard index, id2entry.db4,
exists by default in Directory Server; you do not need to generate it.
The id2entry.db4 contains the actual directory database entries. All other database files can
be recreated from this one.
1.3. Overview of the Searching Algorithm
Indexes are used to speed up searches. To understand how the directory uses indexes, it helps
to understand the searching algorithm. Each index contains a list of attributes (such as the cn,
common name, attribute) and a pointer to the entries corresponding to each value. Directory
Indexes
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