Indexes

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

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HP UX Red Hat Direry Server Software Overview of the Searching Algorithm, Overview of Standard Indexes, System Indexes