Microsoft Sharepoint Products and Technologies Resource Kit eBook

592 Part VII: Information Management in SharePoint Products and Technologies
Removing Words from a Noise Word File A two-step process is needed to allow
a successful search on a word that is listed in a noise word file. First the word must
be removed from the noise word file. Next, the index must be reset and a full update
must be run. In the indexing process, noise words are removed from text before the
text is included in an index. Even after a word is removed from the noise word file,
that word must be integrated into the index. Resetting the index and re-indexing all
content is the only way to accomplish this.
Adding Words to a Noise Word File Adding noise words to a noise word file will
cause those words to be removed from the index. This decreases the size of the
index, which helps performance. It can also decrease the accuracy of the searches
on the index if the added noise word is needed by users.
What kind of words should be added to a noise word file? This will be different
for each environment, but the general rule is that if the word presents no search value
to your users, it can be (and in some cases should be) placed in the noise word file.
For example, your company’s name likely has no real search value because a
search query on your company’s name against all your indexed data will return such
a large result set that the list will be meaningless. Other types of words that can be
placed in the noise word file to ensure that those words do not appear in the index
could include the following types of words:
■ Politically, culturally, or sexually inappropriate or insensitive words
■ Names of high-profile employees, such as the names of CEOs or company
presidents
■ Commonly used product names or generic terms that are specific to your company
or industry
■ Any other words that present no search value in your organization, such as
slang words
Placing a word in the noise word file results in that word not appearing in the
index. In turn, this means that a query against that word will return an empty result set.
Deleting Noise Word Files A noise word file should never be deleted. If you
delete the file, the neutral noise file will be used and all single characters will be
removed as noise words. If you want to include all words in the content index, even
noise words, you should delete all entries from the noise word file for the language
you are using. Leave the empty file in the directory.
PQS Plug-In
The Persistent Query Service (PQS) plug-in is responsible for matching the data
stream from the content source with the alert subscriptions that have been created
by your users. Alerts are really little more than SQL Select Statements that reside in
the SQL databases. The information is filtered through these statements, and when
there is a match, a notification is generated.