Question

I need a SQL query to get the common words only between two sentences. For example:

Sentence 1: This site is very helpful

Sentence 2: I need a helpful site

The result should be: site helpful

Also, if I need to compare sentence 1 to table field records to get the record that contains most common words to sentence 1, what can I do?

Answer 1

You question title says MSQL, so I’m taking your question as a Sql Server question.

1. Split function

Depending on SQL Server version/Server Configuration, you’ll need a split function that can split a string on a delimiter of choice. Here’s such a function.

CREATE FUNCTION [dbo].[fnSplit](@data NVARCHAR(MAX), @delimiter NVARCHAR(5))
RETURNS @t TABLE (rowNum int IDENTITY(1,1), data NVARCHAR(max), descriptor varchar(255) NULL)
AS
BEGIN

    DECLARE @textXML XML;
    SELECT    @textXML = CAST('<d>' + REPLACE(@data, @delimiter, '</d><d>') + '</d>' AS XML);

    INSERT INTO @t(data)
    SELECT  RTRIM(LTRIM(T.split.value('.', 'nvarchar(max)'))) AS data
    FROM    @textXML.nodes('/d') T(split)

    RETURN
END

1. Query for common words using split function (there are quite a few ways to do this, here’s one).
   
SELECT sentence1.data
FROM dbo.fnSplit('This site is very helpful',' ') sentence1
INNER JOIN dbo.fnSplit('I need a helpful site',' ') sentence2 ON sentence1.data = sentence2.data