MySQL aggregation query

MySQL supports multiple aggregation queries, including SUM, COUNT, AVG, MIN, MAX, and more. The following is an example table structure and sample data: Table name: orders |Order_ ID | customer_ Id | order_ Date | amount| |----------|-------------|------------|--------| |1 | 1 | 2022-01-01 | 100| |2 | 1 | 2022-01-02 | 200| |3 | 2 | 2022-01-01 | 150| |4 | 2 | 2022-01-02 | 300| 1. SUM aggregation query: calculating the sum of a certain column sql SELECT SUM(amount) as total_amount FROM orders; Result: total_ Amount=750 2. COUNT aggregation query: calculating the number of a column sql SELECT COUNT(order_id) as total_orders FROM orders; Result: total_ Orders=4 3. AVG aggregation query: calculating the average value of a column sql SELECT AVG(amount) as avg_amount FROM orders; Result: avg_ Amount=187.5 4. MIN aggregation query: finding the minimum value of a certain column sql SELECT MIN(amount) as min_amount FROM orders; Result: min_ Amount=100 5. MAX aggregation query: Find the maximum value of a column sql SELECT MAX(amount) as max_amount FROM orders; Result: max_ Amount=300 In addition to the basic aggregation queries mentioned above, MySQL also supports other advanced aggregation queries, such as GROUP BY, HAVING, etc., which can be used for grouping, filtering, and other operations on data. Here is an example: sql SELECT customer_id, SUM(amount) as total_amount FROM orders GROUP BY customer_id HAVING total_amount > 200; Result: |Customer_ Id | total_ Amount| |-------------|--------------| |1 | 300| |2 | 450| In this example, first press customer on the orders table_ The ID is grouped, and the total amount in each group is calculated, and groups with a total greater than 200 are filtered out.