mysql | Facet search advanced - mysql

Question

I have tables:
CREATE TABLE IF NOT EXISTS `category` (
`id` int(11) NOT NULL,
`name` varchar(255) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
INSERT INTO `category` (`id`, `name`) VALUES
(1, 'Computers'),
(2, 'Bikes');
CREATE TABLE IF NOT EXISTS `fields` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`field_name` varchar(255) DEFAULT NULL,
`cid` text NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=4 ;
INSERT INTO `fields` (`id`, `field_name`, `cid`) VALUES
(1, 'Processor', '1'),
(2, 'Display', '1'),
(3, 'Brand', '2');
CREATE TABLE IF NOT EXISTS `fields_values` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`field_id` int(11) DEFAULT NULL,
`field_value` varchar(255) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=7 ;
INSERT INTO `fields_values` (`id`, `field_id`, `field_value`) VALUES
(1, 1, 'Intel Pentium 3'),
(2, 2, '27 inch'),
(3, 3, 'BMX'),
(4, 1, 'AMD Radeon'),
(5, 1, 'Intel Atom'),
(6, 2, '22 inch');
CREATE TABLE IF NOT EXISTS `products` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) NOT NULL,
`cid` text NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 AUTO_INCREMENT=6 ;
INSERT INTO `products` (`id`, `name`, `cid`) VALUES
(1, 'Computer1', 1),
(2, 'Bike1.BMX', 2),
(3, 'Bike3', 2),
(4, 'Intel Atom', 1),
(5, 'Computer Radeon', 1);
CREATE TABLE IF NOT EXISTS `products_to_fields_values` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`product_id` int(11) DEFAULT NULL,
`field_value_id` int(11) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=5 ;
INSERT INTO `products_to_fields_values` (`id`, `product_id`, `field_value_id`) VALUES
(1, 1, 1),
(2, 2, 3),
(3, 1, 2),
(4, 4, 5);
My request looks like:
SELECT ft.id field_id, ft.field_name, fvt.field_value, fvt.id field_value_id, COUNT( DISTINCT pid ) count
FROM FIELDS ft
JOIN fields_values fvt ON ( ft.id = fvt.field_id )
JOIN products_to_fields_values pfv ON ( pfv.field_value_id = fvt.id )
JOIN products pt ON ( pt.id = pfv.product_id )
LEFT JOIN (
SELECT ft.id field_id, ft.field_name, fvt.field_value, fvt.id field_value_id, pt.name, pt.id pid
FROM FIELDS ft
JOIN fields_values fvt ON ( ft.id = fvt.field_id )
JOIN products_to_fields_values pfv ON ( pfv.field_value_id = fvt.id )
JOIN products pt ON ( pt.id = pfv.product_id )
GROUP BY pt.id
)LJ ON pfv.product_id = LJ.pid
WHERE FIND_IN_SET( 1, pt.cid )
GROUP BY ft.field_name, fvt.field_value
LIMIT 0 , 30
This request will return (I'm trying to build faceted filter):
field_id field_name field_value field_value_id count
2 Display 27 inch 2 1
1 Processor Intel Atom 5 1
1 Processor Intel Pentium 3 1
But I have other values in this table: fields_values like: AMD Radeon and 22 inch.
Where is my mistake in the request?
Thanks!
EDIT:
I'm expect to getting result:
field_id field_name field_value field_value_id count
2 Display 22 inch 6 0
2 Display 27 inch 2 1
1 Processor AMD Radeon 4 0
1 Processor Intel Atom 5 1
1 Processor IntelPentium3 1 1
Where count is a products count.

Answer 1

Here is a work SQL, but im not sure you have build your structure correctly.
SELECT
ft.id field_id, ft.field_name, fvt.field_value, fvt.id as field_value_id, COUNT( DISTINCT pid ) count
FROM products AS pt
JOIN products_to_fields_values AS pfv ON pfv.product_id = pt.id
JOIN fields_values AS fvt ON fvt.field_id = pfv.field_value_id
JOIN fields AS ft on ft.id = fvt.field_id
LEFT JOIN (
SELECT ft.id field_id, ft.field_name, fvt.field_value, fvt.id field_value_id, pt.name, pt.id pid
FROM fields ft
JOIN fields_values fvt ON ( ft.id = fvt.field_id )
JOIN products_to_fields_values pfv ON ( pfv.field_value_id = fvt.id )
JOIN products pt ON ( pt.id = pfv.product_id )
GROUP BY pt.id
)LJ ON pfv.product_id = LJ.pid
WHERE FIND_IN_SET( 1, pt.cid )
GROUP BY ft.field_name, fvt.field_value
LIMIT 0 , 30
In short - u have error in this line:
JOIN products_to_fields_values pfv ON ( pfv.field_value_id = fvt.id )
right one:
JOIN products_to_fields_values pfv ON ( pfv.field_value_id = fvt.field_id )

Answer 2

I tried for your question, check this query
select fValue.field_id, f.field_name as field_name, fValue.field_value, fValue.id as field_value_id
from products_to_fields_values as productValue
left join fields_values as fValue on(fValue.field_id=productValue.field_value_id)
left join fields as f on (fValue.field_id=f.id)
left join products as p on (productValue.product_id=p.id)
where p.cid=1

Answer 3

I am quite sure the problem, i.e. the 'missing' records, is being caused by the 'group by' commands. It's a bit difficult to come up with a solution for you as I am not too sure what you are trying to achieve. The expected result you posted hasn't helped me much in this regard. The query you are trying to run is rather complex, and on a populated database is going to start running very, very slowly. As such it would suggest a better database design is required. If you can explain what you are trying to achieve I will gladly look at a solution for you.

Answer 4

Ignoring the limit and where clauses this is the query you need to use:
SELECT
fields.id AS field_id
, fields.field_name
, fields_values.field_value
, fields_values.id AS field_value_id
, COUNT(products.id) AS `count`
FROM fields_values
JOIN fields ON fields.id = fields_values.field_id
JOIN category AS field_category ON field_category.id = fields.cid
LEFT JOIN products_to_fields_values AS product_fields ON fields_values.id = product_fields.field_value_id
LEFT JOIN products ON products.id = product_fields.product_id
GROUP BY 1, 2, 3, 4;
This produces the following result:
| field_id | field_name | field_value | field_value_id | count |
+----------+------------+-----------------+----------------+-------+
| 1 | Processor | AMD Radeon | 4 | 0 |
| 1 | Processor | Intel Atom | 5 | 1 |
| 1 | Processor | Intel Pentium 3 | 1 | 1 |
| 2 | Display | 22 inch | 6 | 0 |
| 2 | Display | 27 inch | 2 | 1 |
| 3 | Brand | BMX | 3 | 1 |
In your where clause you can specify
WHERE category.id IN (1)
to get the result you want.
The mistake you were making (and a previous answer as well) was that you were joining the category through the product giving you the product_category instead of the field_category.
When you applied a where condition on the product_category, it removed all products not part of the set, so you would never get the count = 0