MySQL教程 SQL 语句 MySQL数据库参考手册

简介管理系统 SQL AND, OR, NOT ORDER BY NULL Values LIMIT MIN 和 MAX COUNT, AVG, SUM LIKE 通配符 IN BETWEEN 别名联接 INNER JOIN LEFT JOIN RIGHT JOIN CROSS JOIN 自联接 UNION GROUP BY HAVING EXISTS ANY, ALL INSERT SELECT CASE Null 函数注释运算符创建数据库删除数据库删除表更改表约束 Not Null Unique Primary Key Foreign Key Check Default Create Index 自动增量日期视图数据类型函数

MySQL教程

简介管理系统

MySQL数据库

创建数据库删除数据库删除表更改表约束 Not Null Unique Primary Key Foreign Key Check Default Create Index 自动增量日期视图

参考手册

数据类型函数

MySQL 教程

更新时间2025-08-20

GROUP BY EXISTS

MySQL HAVING 子句

HAVING 子句已添加到 SQL，因为 WHERE 关键字不能与聚合函数一起使用。

HAVING 语法

SELECT column_name(s) FROM table_name WHERE condition GROUP BY column_name(s)HAVING conditionORDER BY column_name(s);

演示数据库

以下是 Northwind 示例数据库中"Customers"表的选择:

CustomerID	CustomerName	ContactName	Address	City	PostalCode	Country
1	Alfreds Futterkiste	Maria Anders	Obere Str. 57	Berlin	12209	Germany
2	Ana Trujillo Emparedados y helados	Ana Trujillo	Avda. de la Constitución 2222	México D.F.	05021	Mexico
3	Antonio Moreno Taquería	Antonio Moreno	Mataderos 2312	México D.F.	05023	Mexico
4	Around the Horn	Thomas Hardy	120 Hanover Sq.	London	WA1 1DP	UK
5	Berglunds snabbköp	Christina Berglund	Berguvsvägen 8	Luleå	S-958 22	Sweden

MySQL HAVING 示例

以下 SQL 语句列出了每个地区的客户数量。仅包括拥有 5 个以上客户的地区:

实例

SELECT COUNT(CustomerID), CountryFROM CustomersGROUP BY Country HAVING COUNT(CustomerID) > 5;

以下 SQL 语句列出了每个地区的客户数量，从高到低排序（仅包括客户超过 5 个的地区）:

实例

SELECT COUNT(CustomerID), CountryFROM CustomersGROUP BY CountryHAVING COUNT(CustomerID) > 5 ORDER BY COUNT(CustomerID) DESC;

演示数据库

以下是 Northwind 示例数据库中"Orders"表的选择:

OrderID	CustomerID	EmployeeID	OrderDate	ShipperID
10248	90	5	1996-07-04	3
10249	81	6	1996-07-05	1
10250	34	4	1996-07-08	2

以及从"Employees"表中选择的内容:

EmployeeID	LastName	FirstName	BirthDate	Photo	Notes
1	Davolio	Nancy	1968-12-08	EmpID1.pic	Education includes a BA....
2	Fuller	Andrew	1952-02-19	EmpID2.pic	Andrew received his BTS....
3	Leverling	Janet	1963-08-30	EmpID3.pic	Janet has a BS degree....

更多 HAVING 示例

以下 SQL 语句列出了注册超过 10 个订单的员工:

实例

SELECT Employees.LastName, COUNT(Orders.OrderID) AS NumberOfOrdersFROM (OrdersINNER JOIN Employees ON Orders.EmployeeID = Employees.EmployeeID) GROUP BY LastNameHAVING COUNT(Orders.OrderID) > 10;

以下 SQL 语句列出员工"Davolio"或"Fuller"是否已注册超过 25 个订单:

实例

SELECT Employees.LastName, COUNT(Orders.OrderID) AS NumberOfOrdersFROM Orders INNER JOIN Employees ON Orders.EmployeeID = Employees.EmployeeID WHERE LastName = 'Davolio' OR LastName = 'Fuller'GROUP BY LastNameHAVING COUNT(Orders.OrderID) > 25;

GROUP BY EXISTS

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