SQL逻辑查询语句执行顺序

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1. SQL逻辑查询语句执行顺序

2. MySQL联接查询操做

3. MySQL扫盲篇

4. MySQL存储引擎介绍

5. MySQL数据类型和属性

6. MySQL处理数据库和表的经常使用命令

SELECT a.customer_id, COUNT(b.order_id) as total_orders

FROM table1 AS a

LEFT JOIN table2 AS b

ON a.customer_id = b.customer_id

WHERE a.city = 'hangzhou'

GROUP BY a.customer_id

HAVING count(b.order_id) < 2

ORDER BY total_orders DESC;