Describe how to improve the efficiency of SQL statement execution and improve performance?

1. Select the most efficient table name order;

2. The order of connections in the WHERE clause;

3. Avoid using ' * ' in the SELECT clause;

4. Replace the HAVING clause with a WHERE clause;

5. Improve SQL efficiency through internal functions;

6. Avoid the use of calculations on indexed columns;

7. The efficiency of the group BY statement can be improved by filtering out unwanted records before group by.

Describe how to improve the efficiency of SQL statement execution and improve performance?