sql - 总和重复行值

Question

我试图对两行具有重复值的行的值求和，下面是我的表:

表名(客户)

value   years   total
1           30    30
3           10    10
4           15    15
4           25    25

我理想上希望最终拥有:

value  years   total
1      30      30
3      10      10
4      40      40

我尝试使用SELECT DISTINCT和GROUP BY摆脱重复的行，而且下面代码中的联接不是必需的。无论这两个命令都无效。这也是我的代码:

SELECT DISTINCT 
  value,
  years,
  SUM(customer.years) AS total 
FROM customer 
INNER JOIN language 
  ON customer.expert=language.l_id 
GROUP BY 
  expert, 
  years;

但这会产生第一个表的副本，欢迎任何输入。谢谢!!!

Answer 1

SELECT
   value,
   SUM(years) AS years,
   SUM(total) AS total
FROM customers
GROUP BY value;

您需要每个值(按-分组)的年份和总计之和。