Querying data tables is incredibly slow !, Query data tables

Querying data tables is incredibly slow !, Query data tables

 

Summary: a table in the database has a problem, resulting in a very slow query speed!

 

Troubleshooting process:

1. view problems?

2. SQL statement problems?

3. No required indexes have been created?

Later:

After debugging the entire SQL statement in segments, it becomes very difficult to add a table!

Import the table information to a new table and delete the table. The new table cannot be used!

 

A problem exists in the data table !!!

The first time I encountered such a strange problem, I was a cainiao so anxious to cry!