您可以通过简单的连接在单个查询中获得所有信息，例如：
SELECt d.name AS 'department', p.name AS 'name'FROM department d LEFT JOIN people p ON p.department_id = d.idORDER BY department
这将返回所有数据，但是使用起来有些麻烦，因为无论如何您都必须遍历每个人。您可以进一步将它们分组在一起：
SELECt d.name AS 'department', GROUP_CONCAt(p.name SEPARATOR ', ') AS 'name'FROM department d LEFT JOIN people p ON p.department_id = d.idGROUP BY department
您将获得如下内容：
department | name-----------|----------------sales | Tom, Bill, Rachelmarketing | Jessica, John
