Analysis of why the database is slow after migrating to RDS
https://help.aliyun.com/knowledge_detail/5973962.html
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1. View the execution plan of sql through explain.
2. By viewing the monitoring indicators of the database, find the SQL corresponding to the top 5 consumption resources.
3. By checking the slow log of the database, it is found that a large number of slow SQLs are executed, and the execution time exceeds 2S.
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