1. background ： We have received frequent reports through nailing and e-mail since last night cpu The load exceeds 90%, just BI Colleague evening 、 Early in the morning, online audit cooperation is frequent DML database ( remarks ：BI A colleague has a library DML jurisdiction , It will be withdrawn after the audit ) In addition, I have done timing synchronization online and offline, and this kind of thing has also happened before , I didn't take it seriously .
I came to patrol this morning , I found something unusual .
2. The following large number of statements are frequent , Discovery is another library ( Another business , The amount of concurrency is relatively large ), No 1 Why .
explain analysis , Found no index type:ALL
The execution time is 7 More than seconds .
3.desc table structure , Find out ad_id This field was developed and defined before I came here varchar(20),
See here speechless , This table is related to Tiktok and drainage , It was developed before , It is suggested to make it bigint replace varchar(20), Development doesn't need transformation for the time being
See here , You know why , because ad_id Defined by development varchar(20), but sql ad_id After is int type , There's an implicit conversion .
`ad_id` = '1733062082364420' The program has been modified ,cpu The load comes down immediately .
Caused by implicit conversion cpu Load near 100% More articles about
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