Microsoft Full-Text Engine for SQL Server
The Microsoft Full-Text Engine for SQL Server (MSFTESQL) service is a full-text indexing and search engine. The MSFTESQL engine is built on Microsoft Search (MSSearch) technology and is integrated into the Microsoft SQL Server 2005 Database Engine more tightly than ever.
The full-text engine runs as a service named MSFTESQL on the operating system. This service is installed by default but runs only when Full-Text Search is being used. By default, SQL Server and MSFTESQL run under the same service account. You can specify a different account by using SQL Server Configuration Manager.
SQL Server 2005 provides side-by-side installs of the full-text engine. For each instance of SQL Server, there is a dedicated instance of MSFTESQL, including dedicated components such as word breakers and filters, resources such as memory, and configuration such as service-level settings like resource_usage at the instance level.
The MSFTESQL service is responsible for reading from and writing to full-text catalogs, which are not stored in SQL Server, but are stored as a collection of files in the file system. The MSFTESQL service has the following roles:
- Indexing support
The MSFTESQL service is responsible for filtering and tokenizing data provided by the SQL Server full-text gatherer. It also implements the full-text catalogs as inverted index structures on disk.
- Querying support
MSFTESQL processes full-text search queries and determines which entries in the index meet the full-text selection criteria. For each entry that meets the selection criteria, it returns the identity of the row plus a ranking value to the SQL Server service, where this information is used to construct the query result set. The types of queries supported include searching for:
Words or phrases.
Words in close proximity to each other.
Inflectional forms of words.
Thesaurus-based expansion sets.
- Words or phrases.