Microsoft SharePoint Server 2010 can create a searchable index of documents stored either in a file share, in SharePoint Server 2010, or various other file repositories. The process of indexing new documents or content is called Crawling. Crawled properties are metadata (such as author, title, or subject) that are extracted from documents during crawls. Managed properties are metadata that can appear in refined searches.
Searches can be performed only on managed properties, not crawled properties. To make a crawled property available for search queries and display in Advanced Search and search results, you must map it to a managed property. You can map multiple crawled properties to a single managed property or map a single crawled property to multiple managed properties. If a managed property has multiple crawled properties mapped to it, and a document contains values for more than one of the crawled properties, the order in which the properties are mapped and their priority determine the value of the managed property.
For example, three different document types might have different names for the property that identifies the author. One document type might name this property Author, another Writer, and a third Property3. Although all three are crawled properties, only the documents with the Author property appear in search results when a user queries by author. To ensure that all documents appear in search results, map each of these crawled properties to the Author managed property.
Crawled and Managed Properties are managed by the Search Service Application. By default, or when you create a new Search Service Application, there are 11 crawled property categories available in a SharePoint Server 2010 installation.
To learn more about Crawled and Managed Properties, register for the 3-day 10802 Microsoft Enterprise Search for IT Professionals course that covers SharePoint Server 2010 Search and also FAST Search Server 2010 for SharePoint. To register, navigate to www.fastuniversity.com or contact an Education Consultant at email@example.com.
By David Codrington