Understanding Aggregation Query Performance with EXPLAIN in MySQL

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.

Solution:

-- Use EXPLAIN to inspect the execution plan of an aggregation query.
EXPLAIN SELECT CustomerID, SUM(TotalAmount) AS TotalSales
FROM Orders
GROUP BY CustomerID;

Explanation:

• Purpose of the Query:
• To review how MySQL executes an aggregation query calculating total sales per customer.
• Helps identify potential bottlenecks in GROUP BY operations.
• Key Components:
• EXPLAIN : Provides insights into the query execution plan.
• GROUP BY CustomerID : Aggregates sales data for each customer.
• Real-World Application:
• Vital for businesses analyzing customer purchase trends and sales distribution.

Notes:

• Indexing CustomerID can further enhance performance in grouping operations.
• Aggregation queries may be resource-intensive on large datasets.

For more Practice: Solve these Related Problems:

• Write a MySQL query using EXPLAIN to analyze the performance of a query that calculates the total revenue per product from the Sales table.
• Write a MySQL query using EXPLAIN to analyze the performance of a query that calculates the total number of projects per department from the Projects table.
• Write a MySQL query using EXPLAIN to analyze the performance of a query that calculates the total number of orders per product category from the Orders table.
• Write a MySQL query using EXPLAIN to analyze the performance of a query that calculates the total number of customers per city from the Customers table.

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Previous MySQL Exercise: Optimize Query with Date Range Filtering using Index.
Next MySQL Exercise: Analyze Query with ORDER BY and LIMIT using EXPLAIN.