Given the following table (products_filter):
How can I do a SELECT ... FROM products LEFT JOIN products_filter ... in such a way that it only returns products which have ALL the specified (filter_id,filter_value) pairs.
Example: for (filter_id, filter_value) = (1,1),(3,0) it should only return the product with id 90001, because it matches both values.
If the specified filter pairs is restricted to a deifnite number the the following query should work.
Select a. Product_id
From products a
Left outer join
(Select product_id,filter_id,filter_value,count(*)
From product_filter
Where filter_id in (1,1) and filter_value in(3,0)
Group by product_id,filter_id,filter_value
Having count(*)=2)b
On(a.product_id=b.product_id)
As you only said you wanted the PRODUCTS values having the desired filter attributes... I've limited results to just product.*
The below query uses an inline view with the count of distinct filters by product ID. The outer where clause then uses the distinct count (in case duplicate filters could exist for a product) of the filter_IDs.
The # in the where clause should always match the number of where clause paired sets in the inline view.
Your sample data indicated that the paired sets could be a subset of all filters. so this ensures each filter pair (or more) exists for the desired product.
SELECT p.*
FROM products p
LEFT JOIN (SELECT product_ID, count(Distinct filter_ID) cnt
FROM products_Filter
WHERE (Filter_ID = 1 and filter_value = 1)
or (Filter_ID = 3 and filter_value = 0)
GROUP BY Product_ID) pf
on P.Product_ID = PF.Product_ID
WHERE pf.cnt = 2
Related
products
products_prop
specification
now i want to get the product and in cell i want to get array with all products_prop and the name from specification
if i do like this
SELECT *
FROM `products`
INNER JOIN `product_prop`
ON products.id = product_prop.product_id
INNER JOIN `specification`
ON product_prop.specification_id = specification.id
GROUP BY products.name
what i need to do for get 1 row of product and the all product_prop in array with the name of specification?
I have SQL to count products with specific properties. I am using it in the products filter. SQL is very long, but here is the primary part:
SELECT COUNT(products.id) as products_count, property_items.description, property_items.id as id
FROM property_items
INNER JOIN product_properties ON property_items.id = product_properties.property_item_id
INNER JOIN products ON product_properties.product_id
INNER JOIN product_properties pp ON products.id = pp.product_id AND (pp.property_item_id IN ($ids))
GROUP BY property_items.id
HAVING COUNT(pp.id) >= $countIds
This works perfectly when I have only the one element in $ids, but when i choose one more, the result is bad. It looks like the sql returns count of all products with any property from $ids, but I need to count only products that contains all properties.
First get all available properties. On each property join products that contains this property and go back to all properties of this product to check, if product contains already checked properties too. Or it is bad idea? I need to keep primary table (FROM table) as property_items.
I need to get result in this format:
=============================
id|description|products_count
=============================
1 |lorem ipsum|10
-----------------------------
2 |dolore sit |2
Thanks for any idea.
Try to use SELECT COUNT (DISTINCT products.id) as cnt
You can get the product ids that have all the properties by doing:
SELECT pp.property_id
FROM property_items pi INNER JOIN
product_properties pp
ON pi.id = pp.property_item_id INNER JOIN
products p
ON pp.product_id = p.id
WHERE pp.property_item_id IN ($ids)
GROUP BY pp.property_id
HAVING COUNT(DISTINCT pp.property_item_id) = $countIds -- has all of them
Note that I rationalized the joins. I think your simplification of the query wasn't quite right. I also added table aliases, so the query is easier to write and to read.
If you want the count of such products, use a subquery:
SELECT COUNT(*)
FROM (SELECT pp.property_id
FROM property_items pi INNER JOIN
product_properties pp
ON pi.id = pp.property_item_id INNER JOIN
products p
ON pp.product_id = p.id
WHERE find_in_set(pp.property_item_id, $ids)
GROUP BY pp.property_id
HAVING COUNT(DISTINCT pp.property_item_id) = $countIds -- has all of them
) ;
Your problem is probably because of this line:
WHERE pp.property_item_id IN ($ids)
If you are passing $ids as a comma-separated string, then your query will not work. Note the replacement above.
Select distinct is returning indistinct rows. Why?
I want to return distinct shops.
Here is my sql statement:
SELECT
DISTINCT s.*, p.p_id
FROM
shop s
INNER JOIN product_shop ps on s.s_id = ps.s_id
INNER JOIN product p ON p.p_id = ps.p_id
WHERE
s.country = 'new zealand'
Here is the result:
The product (p.p_id) needs to not be distinct, as I want to return a list of shops that have a specific product. But the Shop needs to be distinct.
What am I doing wrong?
Returned rows are distinct. Distinct is applied to all returned row, not to single column. Yes, p_id is same for two rows. But if you compare all columns, there are differences between them.
If you want distinct shops - don't include in select columns from other tables, because it can cause duplicates as in your example.
Simply don't include p.p_id within your selection.
I.e.
SELECT DISTINCT
s.*
FROM shop s
....
Well, If you will look at your entire output, you can see the p_id(the last column) is different for each row. Distinct applies to the entire record, not just one column.
You can either drop the p_id from your select, or use group by and decide which one of the p_id you want, perhaps max? :
SELECT
s.*, max(p.p_id)
FROM
shop s
INNER JOIN product_shop ps on s.s_id = ps.s_id
INNER JOIN product p ON p.p_id = ps.p_id
WHERE
s.country = 'new zealand'
GROUP BY s.id
I have two tables; One contains for products stats and another one contains additional stats
StatsHourly:
id
product_id (can be multiple)
amount
cost
time
StatsValues:
id
product_id (can be multiple)
value (double)
I need to join those two tables and get something like this in the result:
product_id
sum (amount)
sum (cost)
sum (value)
I'm trying to do this:
"SELECT
SUM(s.amount) as amount,
SUM(s.cost) as cost
FROM StatsHourly s
LEFT JOIN (
SELECT
COALESCE(SUM(value), 0) as value
FROM StatsValues
GROUP BY product_id
) value v ON v.product_id = s.product_id
WHERE 1
AND s.product_id = :product_id";
This doesn't work. Could someone show me the right way to do it?
You have an extra comma after as cost:
SUM(s.cost) as cost, <-- here
You also use 2 aliases for the subquery, you should remove value from there:
) value v
You do not use any output from the subquery.
Coalesce() is unnecessary in the subquery.
This works (tested):
SELECT
s.product_id as product_id,
s.amount_s as amount,
s.cost_s as cost,
v.value_v as value
FROM
(SELECT
product_id,
SUM(amount) as amount_s,
SUM(cost) as cost_s
FROM StatsHourly
GROUP BY product_id) as s
LEFT JOIN
(SELECT
product_id,
SUM(value) as value_v
FROM StatsValues
GROUP BY product_id) as v
ON v.product_id = s.product_id;
WHERE s.product_id = 'product_id';
The point is:
As you have multiple equal product_id in BOTH table you have to make two aggregated tables through subqueries that makes the product_id unique and sum all appropriate rows.
After that you can join and you select the already aggregated values.
Regards
Often you need to show a list of database items and certain aggregate numbers about each item. For instance, when you type the title text on Stack Overflow, the Related Questions list appears. The list shows the titles of related entries and the single aggregated number of quantity of responses for each title.
I have a similar problem but needing multiple aggregates. I'd like to display a list of items in any of 3 formats depending on user options:
My item's name (15 total, 13 owned by me)
My item's name (15 total)
My item's name (13 owned by me)
My database is:
items: itemId, itemName, ownerId
categories: catId, catName
map: mapId, itemId, catId
The query below gets: category name, count of item ids per category
SELECT
categories.catName,
COUNT(map.itemId) AS item_count
FROM categories
LEFT JOIN map
ON categories.catId = map.catId
GROUP BY categories.catName
This one gets: category name, count of item ids per category for this owner_id only
SELECT categories.catName,
COUNT(map.itemId) AS owner_item_count
FROM categories
LEFT JOIN map
ON categories.catId = map.catId
LEFT JOIN items
ON items.itemId = map.itemId
WHERE owner = #ownerId
GROUP BY categories.catId
But how do i get them at the same time in a single query? I.e.: category name, count of item ids per category, count of item ids per category for this owner_id only
Bonus. How can I optionally only retrieve where catId count != 0 for any of these? In trying "WHERE item_count <> 0" I get:
MySQL said: Documentation
#1054 - Unknown column 'rid_count' in 'where clause'
Here's a trick: calculating a SUM() of values that are known to be either 1 or 0 is equivalent to a COUNT() of the rows where the value is 1. And you know that a boolean comparison returns 1 or 0 (or NULL).
SELECT c.catname, COUNT(m.catid) AS item_count,
SUM(i.ownerid = #ownerid) AS owner_item_count
FROM categories c
LEFT JOIN map m USING (catid)
LEFT JOIN items i USING (itemid)
GROUP BY c.catid;
As for the bonus question, you could simply do an inner join instead of an outer join, which would mean only categories with at least one row in map would be returned.
SELECT c.catname, COUNT(m.catid) AS item_count,
SUM(i.ownerid = #ownerid) AS owner_item_count
FROM categories c
INNER JOIN map m USING (catid)
INNER JOIN items i USING (itemid)
GROUP BY c.catid;
Here's another solution, which is not as efficient but I'll show it to explain why you got the error:
SELECT c.catname, COUNT(m.catid) AS item_count,
SUM(i.ownerid = #ownerid) AS owner_item_count
FROM categories c
LEFT JOIN map m USING (catid)
LEFT JOIN items i USING (itemid)
GROUP BY c.catid
HAVING item_count > 0;
You can't use column aliases in the WHERE clause, because expressions in the WHERE clause are evaluated before the expressions in the select-list. In other words, the values associated with select-list expressions aren't available yet.
You can use column aliases in the GROUP BY, HAVING, and ORDER BY clauses. These clauses are run after all the expressions in the select-list have been evaluated.
You can sneak a CASE statement inside your SUM():
SELECT categories.catName,
COUNT(map.itemId) AS item_count,
SUM(CASE WHEN owner= #ownerid THEN 1 ELSE 0 END) AS owner_item_count
FROM categories
LEFT JOIN map ON categories.catId = map.catId
LEFT JOIN items ON items.itemId = map.itemId
GROUP BY categories.catId
HAVING COUNT(map.itemId) > 0
SELECT categories.catName,
COUNT(map.itemId) AS item_count,
COUNT(items.itemId) AS owner_item_count
FROM categories
INNER JOIN map
ON categories.catId = map.catId
LEFT JOIN items
ON items.itemId = map.itemId
AND items.owner = #ownerId
GROUP BY categories.catId
Note that you could use a HAVING clause on owner_item_count, but the inner join takes care of item_count for you.