What is the SQL used to do a search similar to "Related Questions" on Stackoverflow

Question

I am trying to implement a feature similar to the "Related Questions" on Stackoverflow.

How do I go about writing the SQL statement that will search the Title and Summary field of my database for similar questions?

If my questions is: "What is the SQL used to do a search similar to "Related Questions" on Stackoverflow".

Steps that I can think of are;

1. Strip the quotation marks
2. Split the sentence into an array of words and run a SQL search on each word.

If I do it this way, I am guessing that I wouldn't get any meaningful results. I am not sure if Full Text Search is enabled on the server, so I am not using that. Will there be an advantage of using Full Text Search?

I found a similar question but there was no answer: similar question

Using SQL 2005

Answer 1

Check out this podcast.

One of our major performance optimizations for the “related questions” query is removing the top 10,000 most common English dictionary words (as determined by Google search) before submitting the query to the SQL Server 2008 full text engine. It’s shocking how little is left of most posts once you remove the top 10k English dictionary words. This helps limit and narrow the returned results, which makes the query dramatically faster.

Answer 2

They probably relate based on tags that are added to the questions...

Answer 3

After enabling Full Text search on my SQL 2005 server, I am using the following stored procedure to search for text.

ALTER PROCEDURE [dbo].[GetSimilarIssues] 
(
 @InputSearch varchar(255)
)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;

DECLARE @SearchText varchar(500);

SELECT @SearchText = '"' + @InputSearch + '*"'

SELECT  PostId, Summary, [Description], 
Created
FROM Issue

WHERE FREETEXT (Summary, @SearchText);
END