Practical Exercises for MySQL Query Optimization
Performance Optimization Exercises with solutions [20 exercises with solution]
1. Analyze Query Performance with EXPLAIN
Write a MySQL query to use EXPLAIN to analyze the performance of a SELECT query retrieving all orders placed after a specific date from the Orders table.
2. Add an Index for Query Optimization
Write a MySQL query to add an index on the CustomerID column in the Orders table to improve query performance.
3. Optimize Query with WHERE Clause using Indexed Column
Write a MySQL query to retrieve all orders for a specific customer from the Orders table, ensuring query optimization by using indexed columns.
4. Remove an unused Index
Write a MySQL query to drop an index that is no longer needed from the Orders table.
5. Create a Composite Index for Enhanced Performance
Write a MySQL query to create a composite index on the CustomerID and OrderDate columns in the Orders table.
6. Analyze JOIN Query Performance with EXPLAIN
Write a MySQL query that uses EXPLAIN to analyze the performance of a JOIN between the Orders and Customers tables.
7. Optimize Query Performance with LIMIT Clause
Write a MySQL query that retrieves the first 10 products from the Products table and uses EXPLAIN to analyze its performance.
8. Force Index usage in a Query
Write a MySQL query that uses FORCE INDEX to force the use of a specific index on the Orders table for improved performance.
9. Analyze Subquery Performance with EXPLAIN
Write a MySQL query that uses EXPLAIN to analyze the performance of a query with a subquery that retrieves orders for customers from Berlin
10. Utilize Covering Index for Query Optimization
Write a MySQL query that selects only indexed columns from the Orders table to leverage a covering index for improved query performance.
11. Optimize Query with Date Range Filtering using Index
Write a MySQL query to retrieve all orders placed between '2025-01-01' and '2025-02-01' from the Orders table, ensuring the query leverages an index on the OrderDate column.
12. Analyze Aggregation Query with EXPLAIN
Write a MySQL query using EXPLAIN to analyze the performance of a query that calculates the total sales per customer from the Orders table.
13. Analyze Query with ORDER BY and LIMIT using EXPLAIN
Write a MySQL query that uses EXPLAIN to analyze a query retrieving the top 5 highest order amounts from the Orders table.
14. Force Index usage in a JOIN Query with Index Hints
Write a MySQL query that uses FORCE INDEX to ensure MySQL uses a specific index on the Orders table when joining with the Customers table.
15. Optimize Query with Covering Index for Aggregation
Write a MySQL query that selects only indexed columns in an aggregation query from the Orders table to benefit from a covering index.
16. Analyze Performance of a Correlated Subquery with EXPLAIN
Write a MySQL query that uses EXPLAIN to analyze a query with a correlated subquery that finds orders with a TotalAmount greater than the average order amount for each customer.
17. Optimize ORDER BY Query using Indexed Column
Write a MySQL query to retrieve all orders sorted by OrderDate from the Orders table, ensuring that the query utilizes an index on the OrderDate column.
18. Analyze Query Performance on a Partitioned Table with EXPLAIN
Write a MySQL query that uses EXPLAIN to analyze the performance of a query on a partitioned Orders table, filtering by a partition key column.
19. Optimize Query with Generated Column and Index
Write a MySQL query to add a generated column based on the OrderDate column in the Orders table and create an index on the new column to optimize queries filtering by month.
20. Analyze Derived Table Query Performance with EXPLAIN
Write a MySQL query that uses EXPLAIN to analyze the performance of a query utilizing a derived table to calculate total orders per customer and then filters for customers with more than 5 orders.
More to Come !
Do not submit any solution of the above exercises at here, if you want to contribute go to the appropriate exercise page.
- Weekly Trends and Language Statistics
- Weekly Trends and Language Statistics