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在对主键的每一行进行分类时,是否在SQL中使用count函数?_Sql - Fatal编程技术网

在对主键的每一行进行分类时,是否在SQL中使用count函数?

在对主键的每一行进行分类时,是否在SQL中使用count函数?,sql,Sql,我正在使用一个表,其中有员工姓名和相应的原籍国。我是SQL新手,所以我想知道如何列出名字以A开头的国家和员工人数 到目前为止我已经知道了,但我正在统计我认为所有员工的人数: SELECT country, count(employee_names) FROM table1 WHERE employee LIKE 'A%' 如何仅获取合并了员工姓名的计数?试试这个 SELECT country, count(employee_names) FROM table1 WHERE employee L

我正在使用一个表,其中有员工姓名和相应的原籍国。我是SQL新手,所以我想知道如何列出名字以A开头的国家和员工人数

到目前为止我已经知道了,但我正在统计我认为所有员工的人数:

SELECT country, count(employee_names)
FROM table1
WHERE employee LIKE 'A%'
如何仅获取合并了员工姓名的计数?

试试这个

SELECT country, count(employee_names)
FROM table1
WHERE employee LIKE 'A%'
Group by country