SQL: Splitting a column into multiple words to search user input - sql

Question

I want to compare the individual words from the user input to individual words from a column in my table.
For example, consider these rows in my table:
ID Name
1 Jack Nicholson
2 Henry Jack Blueberry
3 Pontiac Riddleson Jack
Consider that the user's input is 'Pontiac Jack'. I want to assign weights/ranks for each match, so I can't use a blanket LIKE (WHERE Name LIKE #SearchString).
If Pontiac is present in any row, I want to award it 10 points. Each match for Jack gets another 10 points, etc. So row 3 would get 20 points, and rows 1 and 2 get 10.
I have split the user input into individual words, and stored them into a temporary table #SearchWords(Word).
But I can't figure out a way to have a SELECT statement that allows me to combine this. Maybe I'm going about this the wrong way?
Cheers,
WT

Answer 1

For SQL Server, try this:
SELECT Word, COUNT(Word) * 10 AS WordCount
FROM SourceTable
INNER JOIN SearchWords ON CHARINDEX(SearchWords.Word, SourceTable.Name) > 0
GROUP BY Word

Answer 2

What about this? (this is MySQL syntax, I think you only have to replace the CONCAT and do it with +)
SELECT names.id, count(searchwords.word) FROM names, searchwords WHERE names.name LIKE CONCAT('%', searchwords.word, '%') GROUP BY names.id
Then you would have a SQL result with the ID of the names-table and count of the words that match to that id.

Answer 3

You could do it via a common table expression that works out the weighting. For example:
--** Set up the example tables and data
DECLARE #Name TABLE (id INT IDENTITY, name VARCHAR(50));
DECLARE #SearchWords TABLE (word VARCHAR(50));
INSERT INTO #Name
(name)
VALUES ('Jack Nicholson')
,('Henry Jack Blueberry')
,('Pontiac Riddleson Jack')
,('Fred Bloggs');
INSERT INTO #SearchWords
(word)
VALUES ('Jack')
,('Pontiac');
--** Example SELECT with #Name selected and ordered by words in #SearchWords
WITH Order_CTE (weighting, id)
AS (
SELECT COUNT(*) AS weighting
, id
FROM #Name AS n
JOIN #SearchWords AS sw
ON n.name LIKE '%' + sw.word + '%'
GROUP BY id
)
SELECT n.name
, cte.weighting
FROM #Name AS n
JOIN Order_CTE AS cte
ON n.id = cte.id
ORDER BY cte.weighting DESC;
Using this technique, you can also apply a value to each search word if you wanted to. So you could make Jack more valueable than Pontiac. This would look something like this:
--** Set up the example tables and data
DECLARE #Name TABLE (id INT IDENTITY, name VARCHAR(50));
DECLARE #SearchWords TABLE (word VARCHAR(50), value INT);
INSERT INTO #Name
(name)
VALUES ('Jack Nicholson')
,('Henry Jack Blueberry')
,('Pontiac Riddleson Jack')
,('Fred Bloggs');
--** Set up search words with associated value
INSERT INTO #SearchWords
(word, value)
VALUES ('Jack',10)
,('Pontiac',20)
,('Bloggs',40);
--** Example SELECT with #Name selected and ordered by words and values in #SearchWords
WITH Order_CTE (weighting, id)
AS (
SELECT SUM(sw.value) AS weighting
, id
FROM #Name AS n
JOIN #SearchWords AS sw
ON n.name LIKE '%' + sw.word + '%'
GROUP BY id
)
SELECT n.name
, cte.weighting
FROM #Name AS n
JOIN Order_CTE AS cte
ON n.id = cte.id
ORDER BY cte.weighting DESC;

Answer 4

Seems to me that the best thing to do would be to maintain a separate table with all the individual words. Eg:
ID Word FK_ID
1 Jack 1
2 Nicholson 1
3 Henry 2
(etc)
This table would be kept up to date with triggers, and you'd have a non-clustered index on 'Word', 'FK_ID'. Then the SQL to produce your weightings would be simple and efficient.

Answer 5

How about something like this....
Select id, MAX(names.name), count(id)*10 from names
inner join #SearchWords as sw on
names.name like '%'+sw.word+'%'
group by id
assuming that table with names called "names".