Netscape NETSCAPE DIRECTORY SERVER 6.02, Руководство администратора

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About Indexes
346 Netscape Directory Server Administrator’s Guide • May 2002
2.
The directory examines the incoming request to make sure that the specified
base DN matches a suffix contained by one or more of its databases or database
links.
❍
If they do match, the directory processes the request.
❍
If they do not match, the directory returns an error to the client indicating
that the suffix does not match. If a referral has been specified in the
nsslapd-referral
attribute under
cn=config
, the directory also returns
the LDAP URL where the client can attempt to pursue the request.
3.
If the search request for each database attribute can be satisfied by a single
index, then the server reads that index to generate a list of potential matches.
If there is no index for the attribute, the directory generates a candidate list that
includes all entries in the database which makes the search considerably
slower. (The directory will also do this if the All IDs token is set for the index
key that the server is using. For information on All IDs, see “Managing
Indexes,” on page 367.)
If a search request contains multiple attributes, the directory consults multiple
indexes and then combines the resulting lists of candidate entries.
4.
If there is an index for the attribute, the directory takes the candidate matches
from the index files in the form of a series of entry ID numbers.
5.
The directory uses the returned entry ID numbers to read the corresponding
entries from the
id2entry.db3
file. The Directory Server then examines each
of the candidate entries to see if any match the search criteria. The directory
returns matching entries to the client as each is found.
The directory continues until it has either examined all candidate entries, or
until it reaches the limit set in one of the following attributes:
❍
nsslapd-sizelimit
which specifies the maximum number of entries to
return from a search operation. If this limit is reached, the directory returns
any entries it has located that match the search request, as well as an
exceeded size limit error.
❍
nsslapd-timelimit
which specifies the maximum number of seconds
allocated for a search request. If this limit is reached, the directory returns
any entries it has located that match the search request, as well as an
exceeded time limit error
❍
nsslapd-lookthroughlimi
t which specifies the maximum number of
entries that the directory will check when examining candidate entries in
response to a search request.