You can use SQL Server 2000 to support full-text queries against data in non-text files, too. Document filters that ship with SQL Server 2000 support the capability to search Microsoft Word, Excel, PowerPoint, and HTML files. Other companies have provided document filters to search their products, as well. Adobe, for example, provides a free document filter for indexing .pdf files at http://www.adobe.com/support/downloads/8122.htm.
To implement this, you create a table that contains at least two columns: an image column to hold the data to be searched, and a char(3) column to hold the document type. You store the document type (.pdf, .doc, .htm, .txt) in this char(3) column. SQL Server relies on the document type to choose the document filter to use during indexing operations.