mySQL query: find what contains a keyword and the number of objects having the keyword

hopeless_user :

I need to find all the object's that contain a specific keyword, together with the amount found. I already started with it, but don't know how to find the amount. I properly need to use COUNT but I can't seem to get it to work.

select object
from object o
where o.CTN like '%keyword%';

Another thing is, to only get the CTN that are shared by more than 3.

Sebastian Brosch :

You can try the following:

SELECT object, FLOOR(((CHAR_LENGTH(object) - CHAR_LENGTH(REPLACE(object, 'keyword', ''))) / CHAR_LENGTH('keyword'))) AS cnt_matches
FROM object o
WHERE o.object LIKE '%keyword%'
HAVING cnt_matches > 3

You can also create a function to reuse this expression:

DELIMITER //

CREATE FUNCTION GetStringCount(strValue VARCHAR(200), charValue VARCHAR(200))
RETURNS INTEGER DETERMINISTIC NO SQL
BEGIN
  RETURN (CHAR_LENGTH(strValue) - CHAR_LENGTH(REPLACE(strValue, charValue, ''))) / CHAR_LENGTH(charValue);
END

So your query looks like this:

SELECT object, GetStringCount(object, 'keyword') AS cnt_matches
FROM object o
WHERE o.object LIKE '%keyword%'
HAVING cnt_matches > 3

demo on dbfiddle.uk