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如何在mysql中进行计数_Sql_Mysql_Aggregate Functions - Fatal编程技术网

如何在mysql中进行计数

如何在mysql中进行计数,sql,mysql,aggregate-functions,Sql,Mysql,Aggregate Functions,我有一张“用户”表格 我想数一数ID为1和2的员工的工资 我如何在mysql中计算这一行请看一看,我将让您参考从 SELECT SUM(salary) FROM users WHERE id IN(1, 2); 可能是这样的: SELECT COUNT(*) FROM users WHERE id IN (1,2); 虽然如果你真的想计算工资总额,那么你应该参考 以获得双方的总工资 SELECT SUM(salary) FROM users WHERE id IN(1, 2); 并获得个人

我有一张“用户”表格

我想数一数ID为1和2的员工的工资


我如何在mysql中计算这一行

请看一看,我将让您参考从

SELECT SUM(salary) FROM users WHERE id IN(1, 2);
可能是这样的:

SELECT COUNT(*) FROM users WHERE id IN (1,2);
虽然如果你真的想计算工资总额,那么你应该参考


以获得双方的总工资

SELECT SUM(salary) FROM users WHERE id IN(1, 2);
并获得个人工资总额

SELECT SUM(salary) FROM users WHERE id IN(1, 2) group by id;

计数表示总和,如果是,则使用总和
SELECT SUM(salary) FROM users WHERE id IN(1, 2) group by id;