SQL优化经验

在大数据量、去重的密集度不高的情况下：如下SQL，最后一种写法会更快

select *  from (select distinct app_name as value, app_name as value_en 
from xxx order by app_name)       
where value like CONCAT('%', '直播', '%') OR value_en like CONCAT('%', '直播', '%');

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with apps as (select app_name as value, app_name as value_en from xxx group by app_name order by app_name)
select value, value_en  from apps where value like CONCAT('%', '直播', '%') OR value_en like CONCAT('%', '直播', '%');

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select * from 
(select '直播' as name) a 
left join 
(select app_name as value, app_name as value_en from xxx group by app_name order by app_name) b 
on b.value like CONCAT('%', a.name, '%') or value_en like CONCAT('%', a.name, '%');