Search Technologies for SharePoint 2010 Products

When compared to SharePoint 2007, one more search technology option - FAST Search Server 2010 for SharePoint has been added to SharePoint 2010 product family. Options now available are:

1. Microsoft SharePoint Foundation 2010 search
2. Microsoft Search Server 2010 Express
3. Microsoft Search Server 2010
4. Microsoft SharePoint Server 2010
5. FAST Search Server 2010 for SharePoint

FAST Search Server 2010 for SharePoint provides the high-end search features (check the table below) and can search huge corpus of data extremely fast. It was not part of the Technical Preview but it will be available with public Beta. As of now, there is not much public documentation on it though :-(

The Search Technologies for SharePoint 2010 Products document compares and contrasts the above search technologies. The document covers each technology in brief along with topology options available. Copy-pasted below is the Search Capabilities comparison table from the document:

	SharePoint Foundation 2010	Search Server 2010 Express	Search Server 2010	SharePoint Server 2010	FAST Search Server 2010 for SharePoint
Basic search	ü	ü	ü	ü	ü
Visual Best BetsKeyword terms and synonyms defined by an administrator to enhance search results. For FAST Search Server 2010 for SharePoint only, a section of relevant information is displayed in addition to search results for a keyword term (for example, an image banner or HTML).		Limited	Limited	Limited	ü
ScopesUsers can filter search results by using scopes.		ü	ü	ü	ü
Search enhancements based on user contextScopes Best Bets, visual Best Bets, and document promotions and demotions to a sub-group of employees.					ü
Custom propertiesManage which properties are indexed and how these are treated in search results.		ü	ü	ü	ü
Property extractionExtracts key information (people names, locations, company names) from unstructured text to use as additional managed properties. (Limited: title, author, and date only.)		Limited	Limited	Limited	ü
Query federationFederates results from multiple search sources.		ü	ü	ü	ü
Query suggestionsProvides help with query formulation based on what the user types.		ü	ü	ü	ü
Similar resultsGenerates a new search based on the selected search result.					ü
Sort results on managed properties or rank profilesSort results based on selected managed properties or by FAST Query Language (FQL) formula.					ü
Relevancy tuning by document or site promotionsPromote selected documents or sites as highly relevant results for a keyword. Demote documents or sites to give lower rank. (Limited: promote documents for a given site, not query specific.)		Limited	Limited	Limited	ü
Shallow results refinementRefine results using metadata associated with the top results.		ü	ü	ü	ü
Deep results refinementRefine results using metadata associated with all results.					ü
PreviewersDisplay inline previews of Word, PowerPoint, and Excel files.					ü
Windows 7 federationEnterprise search results are available in Windows desktop search.		ü	ü	ü	ü
People searchSearch users to find people by name or expertise.				ü	ü
Social searchRelevancy is improved by how people interact and relate with content by factoring in social tagging and the relationship of people to content and other people.				ü	ü
Taxonomy integrationTakes advantage of user generated tags. Managed taxonomy influences search rankings and experience.				ü	ü
Multi-tenant hostingData partitioning of crawled data based on tenants.				ü
Rich Web indexing supportIndexing of wide variety of Web content, including Flash.					ü

Item level scale table compares the index scalability: 

	Max Items that can be indexed
Microsoft SharePoint Foundation 2010 search	~ 10 million per search server
Microsoft Search Server Express	~ 300,000 with SQL Server Express, ~ 10 million with SQL Server
Microsoft Search Server 2010	~ 100 million
Microsoft SharePoint Server 2010	~ 100 million
FAST Search Server 2010 for SharePoint	500 million +

HTH