问题
For instance, my query is like the following using SQL Server 2005:
SELECT * FROM Table WHERE FREETEXT(SearchField, 'c#')
I have a full text index defined to use the column SearchField which returns results when using:
SELECT * FROM Table WHERE SearchField LIKE '%c#%'
I believe # is a special letter, so how do I allow FREETEXT to work correctly for the query above?
回答1:
The # char is indexed as punctuation and therefore ignored, so it looks like we'll remove the letter C from our word indexing ignore lists.
Tested it locally after doing that and rebuilding the indexes and I get results!
Looking at using a different word breaker language on the indexed column, so that those special characters aren't ignored.
EDIT: I also found this information:
c# is indexed as c (if c is not in your noise word list, see more on noise word lists later), but C# is indexed as C# (in SQL 2005 and SQL 2000 running on Win2003 regardless if C or c is in your noise word list). It is not only C# that is stored as C#, but any capital letter followed by #. Conversely, c++ ( and any other lower-cased letter followed by a ++) is indexed as c (regardless of whether c is in your noise word list).
回答2:
Quoting a much-replicated help page about Indexing Service query language:
To use specially treated characters such as &, |, ^, #, @, $, (, ), in a query, enclose your query in quotation marks (“).
As far as I know, full text search in MSSQL is also done by the Indexing Service, so this might help.
来源：https://stackoverflow.com/questions/1042/why-doesnt-sql-full-text-indexing-return-results-for-words-containing