加入3代表的MySQL

Question

我在MySQL 5.5 3個表：

產品

id_product int primary 
product_name varchar 
creation_id int (index) 

product_life

id_product_life int primary 
product_event_name varchar 
product_id int (index) 
creation_id int (index) 

DATE_CREATED

id_creation int primary 
date_creation datetime 

• 「creation_id」從產品和product_life表對於DATE_CREATED表的主鍵id_creation外鍵（無約束）
• 「PRODUCT_ID」從product_life表是用於產品的主鍵id_product外鍵（無約束）表

我需要檢索的某一天（date_creation >= '2014-08-01 00:00:00' AND date_creation <= '2014-08-01 23:59:59'）創造出來的產品數量，但這些產品必須有沒有記錄在product_life表有date_creation >= '2014-08-10 00:00:00'

我嘗試了3個表上的INNER JOIN，但它不起作用。謝謝你的幫助。

Answer 1

SELECT * FROM product 
INNER JOIN date_created 
     ON date_created.id_creation = product.id_creation 
WHERE (date_creation >= '2014-08-01 00:00:00' AND date_creation <= '2014-08-01 23:59:59') 
    AND (SELECT COUNT(*) 
     FROM product_life 
     INNER JOIN date_created 
       ON date_created.id_creation = product.id_creation 
     WHERE product_id = product.id_product 
     AND date_creation >= '2014-08-10 00:00:00') = 0