假设有以下数据表"orders"(order_id为主键),记录了订单的信息:
| order_id | customer_id | order_date | amount |
|---|---|---|---|
| 1 | 1001 | 2022-01-01 | 100 |
| 2 | 1002 | 2022-01-02 | 150 |
| 3 | 1001 | 2022-01-03 | 200 |
| 4 | 1003 | 2022-01-04 | 120 |
请选出查询语句,找出每个顾客的订单数量,以及该顾客的第一笔订单的日期()
假设有以下数据表"orders"(order_id为主键),记录了订单的信息:
| order_id | customer_id | order_date | amount |
|---|---|---|---|
| 1 | 1001 | 2022-01-01 | 100 |
| 2 | 1002 | 2022-01-02 | 150 |
| 3 | 1001 | 2022-01-03 | 200 |
| 4 | 1003 | 2022-01-04 | 120 |
请选出查询语句,找出每个顾客的订单数量,以及该顾客的第一笔订单的日期()
SELECT customer_id, COUNT(order_id) as order_count, MIN(order_date) as first_order_date FROM orders GROUP BY customer_id;SELECT customer_id, COUNT(*) as order_count, MIN(order_date) as first_order_date FROM orders GROUP BY customer_id;ELECT customer_id, COUNT(order_id) as order_count, order_date as first_order_date FROM orders GROUP BY customer_id ORDER BY order_date ASC;SELECT customer_id, COUNT(order_id) as order_count, MAX(order_date) as first_order_date FROM orders GROUP BY customer_id;
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