MySQL从快速30K行中选择NOT IN

Question

我的数据库表name_info有30K行＆amp;术语表60K行，当选择不在表中时，服务器CPU上升。

如何才能最好地编写一个快速选择1行的查询？

SELECT slug FROM terms WHERE slug LIKE 'nm%' AND slug NOT IN 
(SELECT imdb_id FROM name_info) LIMIT 1

Answer 1

确保将查询中使用的列编入索引。

SELECT `slug`
FROM `terms` 
LEFT JOIN `name_info`
ON `slug` = `imdb_id`
WHERE slug LIKE 'nm%' 
AND `imdb_id` IS NULL
LIMIT 0,1;

Answer 2

尝试使用不存在

SELECT slug FROM terms WHERE slug LIKE 'nm%' AND not exists
(SELECT 1 FROM name_info where imdb_id = slug) LIMIT 1