Match closest phrase in SQL

Question

I need to write a query in t-sql or linq that matches db records that contain the most of the user input words.

exmaple: nvarchar field in db: "The quick brown fox jumps over the lazy dog"

User input: "brown cow"

The program would match that record because it has the word brown.

let me know if i need to provide more examples.

Answer 1

We generally use a UDF to split a string into tabular data and can use like command for the same.

declare @searchStr nvarchar(100)
set @searchStr = 'brown fox'
selecT T.* from test T, dbo.fnc_SplitSTring(@searchStr,' ')
where   T.name like '%' + token + '%'


CREATE   FUNCTION [dbo].[fnc_SplitString]
(
@InString varchar(8000),
@Delim char(1)
)
RETURNS @Return table
(
Position int identity,
Token varchar(100) -- Maximum token size is 100 chars...
)
As
BEGIN
    Declare @CR varchar(1),
    @LF varchar(1)
    Set @CR = char(10)
    Set @LF = char(13)
    -- 
    If @InString is null return
    -- 
    Declare @Pos int
    Declare @Pattern char(3)
    Set @Pattern = '%' + @Delim + '%'
    -- 
    Declare @Token varchar(30)
    SELECT @InString = @InString + @Delim -- add trailing delimiter
    SELECT @Pos = PATINDEX(@Pattern, @InString)
    WHILE (@Pos <> 0) BEGIN
     SELECT @Token = ltrim(rtrim(SUBSTRING(@InString, 1, @Pos - 1)))
     Select @Token = replace(@Token, @CR, '')
     Select @Token = replace(@Token, @LF, '')
     Insert @Return Values (@Token)
     SELECT @InString = STUFF(@InString, 1, PATINDEX(@Pattern, @InString),'')
     SELECT @Pos = PATINDEX(@Pattern, @InString)
    END
-- 
return
-- 
END

Answer 2

Assuming you're using T-SQL in a MS SQL Server environment, then you should use Full Text Search technology. It gives you the speed and keeps you away from reinventing the wheel.