Question

我有我的sql查询非常肤色和日常数据表geeting更大，所以查询的执行变得更大所以我需要乐观我的查询。请帮忙

我的查询是

SELECT * FROM tablename 
        WHERE col1 NOT IN (
        SELECT col1 FROM data_visit_aavaas 
        GROUP BY col1 HAVING COUNT(*) >1) 
        AND add_date Like '2017-05-18' 
        ORDER BY add_date ASC

Answer 1

您可以使用NOT EXISTS和DATE函数来使用MySQL索引，例如：

SELECT t.* 
FROM tablename t
WHERE DATE(t.add_date) = '2017-05-18' 
AND NOT EXISTS (
 SELECT 1 FROM data_visit_aavaas WHERE col1 = t.col1
);

进行简单的查询

1 个答案: