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POCounting products associated with hierarchical category listing
 

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  1. POCounting products associated with hierarchical category listing
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    <p><strong>What I have:</strong> </p> <p>A table of categories listed Hierarchically: <img src="https://i.stack.imgur.com/2SMUp.png" alt="category table"></p> <p>A table of products. the column <code>category_id</code> refers to <code>category.id</code>: <img src="https://i.stack.imgur.com/kVoyt.png" alt="enter image description here"></p> <p><strong>What I am trying to do:</strong></p> <p>I am trying to design a query that will count products of catogries withing specified <code>lft</code> and <code>rgt</code> values.<br> for example: between <code>lft</code> = <code>2</code> and <code>rgt</code> = <code>11</code> there are 3 "Immediate subcategories" whose IDs are <code>3</code>, <code>4</code> and <code>5</code>. See that <code>wireless</code> subcategory is not included as it is not an immediate subcategory within the range of <code>lft</code> and <code>rgt</code> but the products of this subcategory will be counted as part of its immediate subcategory which is <code>headphone</code> as you can see from the picture below. <code>Headphone</code> has one direct product and another product relates to its <code>wireless</code> subcategory. </p> <p>the result should be: </p> <p><img src="https://i.stack.imgur.com/ymqtn.png" alt="enter image description here"></p> <p>I have managed to make a query that retrieves immediate sub-categories within specified <code>lft</code> and <code>rgt</code> values. </p> <pre><code> SELECT node.name,node.id, (COUNT(parent.name) - 1) AS depth FROM category AS node, category AS parent WHERE node.lft BETWEEN parent.lft AND parent.rgt AND parent.lft BETWEEN {$lft} AND {$rgt} GROUP BY node.name HAVING depth = 1 ORDER BY node.lft </code></pre> <p>This query will retrieve the sub-catogries like in the last picture when <code>lft</code> = <code>2</code> and <code>rgt</code> = <code>11</code> but it is missing the count.</p> <p>I have experimenting to get that table of results right for quite a while and this is what I came up with but unfortunately it does not work well for some reason I do not know. I appreciate any help regarding this. </p> <pre><code> SELECT parent.name, COUNT(product.category_id) FROM category AS node1 , product, ( SELECT node.name,node.id,node.lft,node.rgt, (COUNT(parent.name) - 1) AS depth FROM category AS node, category AS parent WHERE node.lft BETWEEN parent.lft AND parent.rgt AND parent.lft BETWEEN {$lft} AND {$rgt} GROUP BY node.name HAVING depth = 1 ORDER BY node.lft ) as parent WHERE node1.lft BETWEEN parent.lft AND parent.rgt AND node1.id = product.category_id GROUP BY parent.lft ORDER BY parent.lft </code></pre> <p><strong>UPDATE:</strong> I tried to make SQL fiddle but I got huge list of errors:</p> <pre><code> CREATE TABLE category ( id int auto_increment primary key, name varchar(20), lft varchar(20), rgt varchar(20) ); INSERT INTO category (name, lft,rgt) VALUES ('ELECTRONICS','1','18'), ('TV &amp; audio','2','11'), ('Home theater','3','4'), ('Blu-ray','5','6'), ('Headphone','7','10'), ('Wireless','8','9'), ('Gaming','12','17'), ('Game consoles','13','14'), ('Video games','15','16'); CREATE TABLE product ( id int auto_increment primary key, name varchar(20), category_id varchar(20) ); INSERT INTO product (category_id, name) VALUES ('4','Sony Blu-ray player'), ('5','Beats Solo HD'), ('6','Beats Solo HD wireless'), ('8','PlayStation'), ('8','Xbox'); </code></pre>
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    1. USSami Al-Subhi
    1. USSami Al-Subhi
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      1. POCounting products associated with hierarchical category listing
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      1. VTUpMod
    2. VO
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    1. COCan you make an sqlfiddle example
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      1. USskv
    2. COI will try now.
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      1. USSami Al-Subhi
    3. CO@skv see the update.
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      1. USSami Al-Subhi
 

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