mysql inner join condition to ignore duplicate ids - mysql

Question

Given below the list of tables.
Order the shop ids in the descending order based on the sum of number of clicks for a product in the locations [23,24,25,26,27].
Given product_id = 8
link_shops_locations
shop_id | location_id
---------------------
1 | 23
2 | 24
3 | 25
3 | 26
3 | 27
products_clicks
shop_id | product_id | clicks
-----------------------------
1 | 8 | 1
2 | 7 | 3
2 | 8 | 87
3 | 8 | 21
3 | 8 | 9
link_products_shops
product_id | shop_id
---------------------
7 | 1
8 | 1
8 | 1
8 | 2
8 | 2
8 | 1
7 | 3
8 | 3
This is what I have tried,
SELECT SUM(c.clicks) as no,
s.shop_id
FROM link_products_shops l
INNER JOIN products_clicks c
ON c.product_id = l.product_id
INNER JOIN link_shops_locations s
ON s.shop_id = c.shop_id // duplicate shop_ids gives wrong SUM
WHERE s.location_id IN (23,24,25,26,27)
GROUP BY s.shop_id
ORDER BY no DESC;
My problem is, since the link_shops_locations table has 3 shop_ids, the resulting expected SUM is multiplied by 3. How do I solve this? The INNER JOIN condition of link_shops_locations has something to do with this?. A little help will be very useful.

Answer 1

[1]You missed one more condition in INNER JOIN with products_clicks.
[2]Also you ignored product_id. Have a look at this query.
[3]You had inserted product_id=8 and shop_id=1 three times in link_products_shops table.
select shop_id, SUM(NoOfClicks) FROM(SELECT distinct c.shop_id, c.clicks AS NoOfClicks
FROM products_clicks c
INNER JOIN link_products_shops l
ON c.product_id = l.product_id
AND c.shop_id = l.shop_id
INNER JOIN link_shops_locations s
ON s.shop_id = c.shop_id and s.shop_id = l.shop_id
WHERE s.location_id IN (23,24,25,26,27)
AND c.product_id = 8) AS TabShopCounters
GROUP BY shop_id
ORDER BY NoOfClicks DESC;
SQL Fiddle - http://www.sqlfiddle.com/#!2/b22fe/8