將多個NOT IN轉換爲LEFT JOIN以提高性能

Question

我有這個需要很長時間執行的SQL查詢。

SELECT DISTINCT p.products_id, 
       p.products_group, 
       p.products_quantity, 
       p.products_length, 
       p.products_price, 
       p.products_height, 
       p.products_width, 
       p.products_weight, 
       p.products_cost, 
       p.products_rmb_cost, 
       p.products_best_rmb, 
       p.products_status, 
       p.products_image, 
       p.products_vendor_code, 
       p.products_date_added, 
       pd.products_name 
FROM products p, 
     products_description pd 
WHERE p.products_id = pd.products_id 
     AND p.products_id NOT IN(SELECT related_products_id 
           FROM products_related 
           WHERE products_id = '93667') 
     AND p.products_id NOT IN(SELECT products_id 
           FROM products_related 
           WHERE related_products_id = '93667') 
     AND p.products_group = '300' 
     AND language_id = 1 
     AND (((pd.products_name LIKE '%emerald%') 
       OR p.products_image LIKE '%emerald%' 
       OR p.products_id LIKE '%emerald%') 
      AND ((pd.products_name LIKE '%square%') 
        OR p.products_image LIKE '%square%' 
        OR p.products_id LIKE '%square%')) 
     AND pd.products_id != '93667' 
ORDER BY p.products_group, 
      p.products_quantity, 
      p.products_id 

我試圖向2轉換NOT IN部分LEFT JOIN的而不是提高性能，但是我雖然性能確實大幅提高，我得到的結果是不一樣的原始查詢。 關於如何正確修改此查詢以使用LEFT JOIN而不是NOT IN的任何建議？

編輯：

這是我嘗試過，但得到錯誤的結果：

SELECT DISTINCT p.products_id, 
       p.products_group, 
       p.products_quantity, 
       p.products_length, 
       p.products_price, 
       p.products_height, 
       p.products_width, 
       p.products_weight, 
       p.products_cost, 
       p.products_rmb_cost, 
       p.products_best_rmb, 
       p.products_status, 
       p.products_image, 
       p.products_vendor_code, 
       p.products_date_added, 
       pd.products_name 
FROM products p, 
     products_description pd 
     LEFT JOIN products_related pr 
       ON pr.products_id = '93667' 
       AND pr.related_products_id = '93667' 
WHERE p.products_id = pd.products_id 
     AND pr.products_id IS NULL 
     AND pr.related_products_id IS NULL 
     AND p.products_group = '300' 
     AND language_id = 1 
     AND (((pd.products_name LIKE '%emerald%') 
       OR p.products_image LIKE '%emerald%' 
       OR p.products_id LIKE '%emerald%') 
      AND ((pd.products_name LIKE '%square%') 
        OR p.products_image LIKE '%square%' 
        OR p.products_id LIKE '%square%')) 
     AND pd.products_id != '93667' 
ORDER BY p.products_group, 
      p.products_quantity, 
      p.products_id 

Answer 1

下面嘗試轉換查詢到左join-

SELECT DISTINCT p.products_id, 
       p.products_group, 
       p.products_quantity, 
       p.products_length, 
       p.products_price, 
       p.products_height, 
       p.products_width, 
       p.products_weight, 
       p.products_cost, 
       p.products_rmb_cost, 
       p.products_best_rmb, 
       p.products_status, 
       p.products_image, 
       p.products_vendor_code, 
       p.products_date_added, 
       pd.products_name 
FROM products p 
JOIN products_description pd ON p.products_id = pd.products_id 
LEFT JOIN products_related pr1 ON p.products_id=pr1.related_products_id AND pr1.products_id = '93667' 
LEFT JOIN products_related pr2 ON p.products_id=pr2.products_id AND pr2.related_products_id = '93667' 
WHERE p.products_group = '300' 
     AND language_id = 1 
     AND (((pd.products_name LIKE '%emerald%') 
       OR p.products_image LIKE '%emerald%' 
       OR p.products_id LIKE '%emerald%') 
      AND ((pd.products_name LIKE '%square%') 
        OR p.products_image LIKE '%square%' 
        OR p.products_id LIKE '%square%')) 
     AND pd.products_id != '93667' 
     AND pr1.related_products_id IS NULL 
     AND pr2.products_id IS NULL 
ORDER BY p.products_group, 
      p.products_quantity, 
      p.products_id