Find best intersect (most elements) between Order (haystack) and Pricerules (needle)

Question

Full disclosure I have posted a greater scoped question at SO a couple of days ago with a bounty (no answers yet).

Scope here

How can a CTE be used to find a match with the most elements? For the order 403 i want to find out

• which pricerule is an INTERSECT for all features ordered (FeatureId in (1,2,3))
• for a given featureId (1).

For FeatureId = 1 and OrderId=403 the best matching pricerule is PriceRuleId = 103.

From table OrderPositions

And table FeatureCombinations

I want to find each set (pair) with the most elements in both tables.

SQL Statemens to create the tables with records

Create tables

CREATE TABLE FeatureCombinations(
  PriceRuleId INTEGER,
  FeatureId   INTEGER   
);

CREATE TABLE OrderPositions(
  Id INTEGER  PRIMARY KEY, 
  OrderId   INTEGER,   
  FeatureId   INTEGER
);

Create records

INSERT INTO FeatureCombinations (PriceRuleId, FeatureId)
VALUES (101, 1), (102, 1), (102, 2),
       (103, 1), (103, 2),(103, 3), 
       (105, 7), (106, 7), (106, 8); 
       
INSERT INTO OrderPositions(Id, OrderId, FeatureId)
VALUES (211, 401, 1), (221, 402, 1),(222, 402, 2),
(231, 403, 1),(232, 403, 2),(233, 403, 3);         
   

This is my query attempt but it runs forever so it must be wrong

-- DANGER  runs forever
WITH RECURSIVE cte_OrderPositions (PriceRuleId, FeatureId) AS (
    SELECT fc.PriceRuleId, op.FeatureId
    FROM OrderPositions op LEFT JOIN FeatureCombinations fc
    ON op.FeatureId = fc.FeatureId
    WHERE op.OrderId = 403 
  
    UNION ALL
  
    SELECT c.PriceRuleId, op.FeatureId
    FROM OrderPositions op
    JOIN cte_OrderPositions c ON c.FeatureId = op.FeatureId 
    -- DANGER  runs forever
)

SELECT * FROM cte_OrderPositions;
-- DANGER  runs forever