Question 20081 in Mysql Question posted in
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Is it the right way to use 2 IN in one SQL-query instead of INTERSECT? – Mysql

I have a product filter based on data from multiple tables.

I make query using IN 2 and more times in one query. This works great and only selects products that have

  • and needed attributes
  • and needed options
  • and needed categories
SELECT COUNT(*) FROM `test_oc_product` 
WHERE product_id IN ( 
                        SELECT product_id 
                        FROM test_oc_product_option 
                        WHERE option_id = '21' AND value = 'Red'  
                    )
AND product_id IN ( 
                        SELECT product_id 
                        FROM test_oc_product_attribute 
                        WHERE attribute_id = '10' 
                )

Also I found INTERSECT operator. But there are some nuances

— works ok

(SELECT product_id FROM `test_oc_product`)
INTERSECT
    (SELECT product_id 
    FROM test_oc_product_attribute 
    WHERE attribute_id = '10')
INTERSECT
    (SELECT product_id 
    FROM test_oc_product_option 
    WHERE option_id = '21' 
    AND value = 'Red')

— doesn’t work

(SELECT * FROM `test_oc_product`)
INTERSECT
    (SELECT product_id 
    FROM test_oc_product_attribute 
    WHERE attribute_id = '10'
    )
INTERSECT
    (SELECT product_id 
    FROM test_oc_product_option 
    WHERE option_id = '21' AND value = 'Red'
    )

— doesn’t work

(SELECT COUNT(*) FROM `test_oc_product`)
INTERSECT
    (SELECT product_id 
    FROM test_oc_product_attribute 
    WHERE attribute_id = '10'
    )
    
INTERSECT
    (SELECT product_id 
    FROM test_oc_product_option 
    WHERE option_id = '21' AND value = 'Red'
    )

I not found such examples with IN operator on the Internet. Is it OK to use IN 2 or more times in one sql-query?

I need to select only those products that match the given parameters. And these parameters are stored in different tables

There is a dump with some tables in an abbreviated form

CREATE TABLE test_oc_product (
  product_id int(11) NOT NULL AUTO_INCREMENT,
  model varchar(64) NOT NULL,
  sku varchar(64) NOT NULL,
   PRIMARY KEY (product_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO test_oc_product (product_id, model, sku) VALUES
(1, 'A1', 'A1'),
(2, 'A2', 'A2'),
(3, 'A3', 'A3'),
(4, 'AA', 'AA'),
(5, 'A5', 'A5'),
(6, 'A6', 'A6'),
(7, 'A7', 'A7'),
(8, 'A8', 'A8');

CREATE TABLE test_oc_product_attribute (
  product_id int(11) NOT NULL,
  attribute_id int(11) NOT NULL,
  text text NOT NULL,
  PRIMARY KEY (product_id, attribute_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO test_oc_product_attribute (product_id, attribute_id, text) VALUES 
('1', '10', 'Attribute Value 1'), 
('2', '11', 'Attribute Value 2');


CREATE TABLE test_oc_product_option (
  product_option_id int(11) NOT NULL AUTO_INCREMENT,
  product_id int(11) NOT NULL,
  option_id int(11) NOT NULL,
  value text NOT NULL,
   PRIMARY KEY (product_option_id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


INSERT INTO test_oc_product_option (product_option_id, product_id, option_id, value) VALUES 
(NULL, '1', '21', 'Red'), 
(NULL, '2', '21', 'Red'),
(NULL, '3', '21', 'Blue'),
(NULL, '4', '10', 'S');
Tags:

2

Answers


  1. 0

    As I mentioned in the comments, you need the same number of columns to use intersect.

    Why not try using JOIN instead like this:

    SELECT COUNT(DISTINCT p.product_id) FROM test_oc_product AS p
JOIN test_oc_product_option AS po ON p.product_id = po.product_id
JOIN test_oc_product_attribute AS pa ON p.product_id = pa.product_id
WHERE po.option_id = '21' AND po.value = 'Red'
AND pa.attribute_id = '10';

    NOTE

    Kudos to @TimBiegeleisen for noticing and provided a fix

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  2. 0

    There is nothing wrong per se in using IN more than once in the same query. For reference, I would probably use your first version, refactored to use EXISTS instead of IN:

    SELECT COUNT(*)
FROM test_oc_product op
WHERE EXISTS (
    SELECT 1
    FROM test_oc_product_option opp
    WHERE opp.product_id = op.product_id AND opp.option_id = '21' AND opp.value = 'Red'  
) AND EXISTS (
    SELECT 1
    FROM test_oc_product_attribute opa
    WHERE opa.product_id = op.product_id AND opa.attribute_id = '10' 
);

    For performance, the following two indices should speed up the two exists subqueries:

    CREATE INDEX idx_opp ON test_oc_product_option (product_id, option_id, value);
CREATE INDEX idx_opa ON test_oc_product_attribute (product_id, attribute_id);
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