解决MySQL中的ERROR 1111 (HY000):无效的分组函数使用?如何正确使用带有where子句的聚合函数?
为了在MySQL中正确使用带有where子句的聚合函数,以下是语法-
select *from yourTableName
where yourColumnName > (select AVG(yourColumnName) from yourTableName);
为了理解上述概念,让我们创建一个表。创建表的查询如下-
mysql> create table EmployeeInformation
-> (
-> EmployeeId int,
-> EmployeeName varchar(20),
-> EmployeeSalary int,
-> EmployeeDateOfBirth datetime
-> );
Query OK, 0 rows affected (1.08 sec)
现在,您可以使用insert命令在表中插入一些记录。查询如下-
mysql> insert into EmployeeInformation values(101,'John',5510,'1995-01-21');
Query OK, 1 row affected (0.13 sec)
mysql> insert into EmployeeInformation values(102,'Carol',5600,'1992-03-25');
Query OK, 1 row affected (0.56 sec)
mysql> insert into EmployeeInformation values(103,'Mike',5680,'1991-12-25');
Query OK, 1 row affected (0.14 sec)
mysql> insert into EmployeeInformation values(104,'David',6000,'1991-12-25');
Query OK, 1 row affected (0.23 sec)
mysql> insert into EmployeeInformation values(105,'Bob',7500,'1993-11-26');
Query OK, 1 row affected (0.16 sec)
使用select语句从表中显示所有记录。查询如下-
mysql> select *from EmployeeInformation;
以下是输出结果-
+------------+--------------+----------------+---------------------+
| EmployeeId | EmployeeName | EmployeeSalary | EmployeeDateOfBirth |
+------------+--------------+----------------+---------------------+
| 101 | John | 5510 | 1995-01-21 00:00:00 |
| 102 | Carol | 5600 | 1992-03-25 00:00:00 |
| 103 | Mike | 5680 | 1991-12-25 00:00:00 |
| 104 | David | 6000 | 1991-12-25 00:00:00 |
| 105 | Bob | 7500 | 1993-11-26 00:00:00 |
+------------+--------------+----------------+---------------------+
5 rows in set (0.00 sec)
以下是使用带有where子句的聚合函数的正确方法。查询如下-
mysql> select *from EmployeeInformation
-> where EmployeeSalary > (select AVG(EmployeeSalary) from EmployeeInformation);
以下是输出结果-
+------------+--------------+----------------+---------------------+
| EmployeeId | EmployeeName | EmployeeSalary | EmployeeDateOfBirth |
+------------+--------------+----------------+---------------------+
| 105 | Bob | 7500 | 1993-11-26 00:00:00 |
+------------+--------------+----------------+---------------------+
1 row in set (0.04 sec)
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