About Indexes
Chapter 10
Managing Indexes
395
Balancing the Benefits of Indexing
Before you create new indexes, balance the benefits of maintaining indexes against
the costs. Keep in mind that:
• Approximate indexes are not efficient for attributes commonly containing
numbers, such as telephone numbers.
• Substring indexes do not work for binary attributes.
• Equality indexes should be avoided if the value is big (such as attributes
intended to contain photographs or passwords containing encrypted data).
• Maintaining indexes for attributes not commonly used in a search increases
overhead without improving global searching performance.
• Attributes that are not indexed can still be specified in search requests,
although the search performance may be degraded significantly, depending on
the type of search.
• The more indexes you maintain, the more disk space you will require.
The following example illustrates exactly how time-consuming indexes can
become. Consider the procedure for creating a specific attribute:
1.
The Directory Server receives an add or modify operation.
2.
The Directory Server examines the indexing attributes to determine whether an
index is maintained for the attribute values.
3.
If the created attribute values are indexed, then the Directory Server generates
the new index entries.
4.
Once the server completes the indexing, the actual attribute values are created
according to the client request.
For example, suppose the Directory Server is asked to add the entry
Bertha Sarette
(BR0 SRT)
No match. The code BR0 does not exist in
the original name.
Sarette, Alice
(SRT ALS)
No match. The codes are not specified in
the correct order.
Name in the Directory
(Phonetic Code)
Query String
(Phonetic code)
Match Comments
Содержание DIRECTORY SERVER 7.1
Страница 1: ...Administrator s Guide Red Hat Directory Server Version7 1 May 2005 Updated February 2009 ...
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Страница 78: ...Maintaining Referential Integrity 78 Red Hat Directory Server Administrator s Guide May 2005 ...
Страница 200: ...Assigning Class of Service 200 Red Hat Directory Server Administrator s Guide May 2005 ...
Страница 278: ...Compatibility with Earlier Releases 278 Red Hat Directory Server Administrator s Guide May 2005 ...
Страница 374: ...Troubleshooting Replication Related Problems 374 Red Hat Directory Server Administrator s Guide May 2005 ...
Страница 478: ...Using the Management Information Base 478 Red Hat Directory Server Administrator s Guide May 2005 ...
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Страница 528: ...PTA Plug in Syntax Examples 528 Red Hat Directory Server Administrator s Guide May 2005 ...
Страница 545: ...About Windows Sync Chapter 18 Windows Sync 545 Figure 18 1 Active Directory Directory Server Synchronization Process ...
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Страница 586: ...Storing Information in Multiple Languages 586 Red Hat Directory Server Administrator s Guide May 2005 ...
Страница 606: ...Searching an Internationalized Directory 606 Red Hat Directory Server Administrator s Guide May 2005 ...
Страница 612: ...Examples of LDAP URLs 612 Red Hat Directory Server Administrator s Guide May 2005 ...
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