Microsoft Sharepoint Products and Technologies Resource Kit eBook

594 Part VII: Information Management in SharePoint Products and Technologies
Therefore, crawled information is held in two places—the SPS.EDB ESE (Extensible
Storage Engine) database and the index files or catalogs on the NTFS file system.
If you encounter errors in the gatherer crawling process, these errors will be
recorded in the gatherer logs, which will be discussed later in this chapter.
Adding File Types to the Indexing Process
The extension, or file type, of a file indicates to SharePoint Portal Server which filter it
should use to convert the text in the file to a Unicode character string. File types determine
which IFilter will convert the document in the indexing process. Administrators
can also add new file types so that they can be included in the indexing process. If the
file’s extension does not appear in the File Type list, those files will not be crawled by
the gatherer. The file type can be associated with an existing IFilter; however, IFilters
are designed to filter documents in only one format. If the new file extension is from
an application that does not have an IFilter, it cannot be properly indexed. SharePoint
Portal Server also accepts third-party IFilters for custom file types.
When a file type is added it applies only to content that is stored outside the
portal site and included in the content index through content sources. Therefore, as
long as you have a protocol handler to connect to an external content source, an
IFilter to extract the data from the documents in that content source, and the file
type added to the portal site, then those documents should be available for crawling,
indexing, and searching.
You can add file types to be included in the content index. All files with a
file extension in the list will be included in the index. When you add a file type to
SharePoint Portal Server 2003 and register its IFilter, the file type is readable/searchable
by the portal site. After adding a new file type, it appears on the Include File
Types page.
If you delete a file type, the file format is no longer compatible with or searchable
from SharePoint Portal Server 2003. Changes in file types will not take effect in
the index until you have run a full index on all your content sources. So plan your
file types carefully and give yourself time for new file types to be included in the
index as you execute new Full Updates on your content sources.
Note You must register the IFilter for new file types. If you add a new file
type but no IFilter is registered, only the file properties are included in the
index.
To add a file type
1. On the Site Settings page, in the Search Settings and indexed content section,
click Configure search and indexing.