About Index Types - Netscape DIRECTORY SERVER 6.2 - ADMINISTRATOR Administrator's Manual

About Indexes

About Index Types

Indexes are stored in files in the directory's databases. The names of the files are
based on the indexed attribute, not the type of index contained in the file. Each
index file may contain multiple types of indexes if multiple indexes are maintained
for the specific attribute. For example, all indexes maintained for the common
name attribute are contained in the
Directory Server supports the following types of index:
• Presence index (pres)—The presence index contains a list of the entries that
contain a particular attribute. This index is useful if, for example, you want to
examine any entries that contain access control information. Generating an
aci.db3
search for
The presence index is not used for base object searches.
• Equality index (eq)—The equality index allows you to search efficiently for
entries containing a specific attribute value. For example, an equality index on
the
more efficiently.
• Approximate index (approx)—The approximate index allows efficient
approximate or "sounds-like" searches. For example, an entry may include the
attribute value
value for searches against
Similarly, a search against
return entries including
• Substring index (sub)—The substring index is a costly index to maintain, but it
allows efficient searching against substrings within entries. Note that substring
indexes are limited to a minimum of three characters for each entry.
For example, searches of the form
cn=*derson
would match the common names containing strings such as
Bill Anderson
Jill Anderson
Steve Sanderson
Similarly, the search for
telephonenumber= *555*
364 Netscape Directory Server Administrator's Guide • December 2003
file that includes a presence index lets you efficiently perform the
to generate the Access Control List for the server.
ACI=*
attribute allows a user to perform the search for
cn
cn=Robert E Lee
l=San Francisco
file.
cn.db3
. An approximate search would return this
,
cn~=Robert Lee cn~=Robert
(note the misspelling) would
l~=San Fransisco
.
far
cn=Babs Jensen
, or .
cn~=Lee