如何優化這個沒有關鍵字和ips重複的mysql查詢？

Question

SELECT 
COUNT(keywords) AS count_keywords 
FROM (
    SELECT * FROM keyword_searches GROUP BY keywords, ip 
) tmp_table 
WHERE created_at BETWEEN '2012-03-31 00:00:00' AND '2015-03-31 23:59:59'; 

如何優化此查詢？

Answer 1

首先在內部查詢中使用where條件篩選記錄，然後在外部查詢中計數keywords。

SELECT 
COUNT(keywords) AS count_keywords 
FROM (
    SELECT * FROM keyword_searches WHERE created_at BETWEEN '2012-03-31 00:00:00' AND '2015-03-31 23:59:59' GROUP BY keywords, ip 
) tmp_table ; 

你的情況，你有未滿足條件BETWEEN '2012-03-31 00:00:00' AND '2015-03-31 23:59:59'