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如何从alias查找mysql中的总计(总和)?_Mysql_Database_Mysql Workbench - Fatal编程技术网

如何从alias查找mysql中的总计(总和)?

如何从alias查找mysql中的总计(总和)?,mysql,database,mysql-workbench,Mysql,Database,Mysql Workbench,事实上,我有原始数据库 SELECT sum(data1,data2) as database_value,sum(data3,data4) as database_not_value from table_name; | ID | science_name_short |database_value | database_not_value| | 1 | Rhododendron phipli |3 | 4 |

事实上,我有原始数据库

SELECT sum(data1,data2) as database_value,sum(data3,data4) as database_not_value  from table_name;

| ID | science_name_short    |database_value   | database_not_value| 
|  1 | Rhododendron phipli   |3                | 4                 |  
|  2 | Rhododendron felica   |5                |6                  |  
| 3  | Rhododendron deron    |5                | 7                 |   
| 4  | Rhododendron  sednuns |5                |8                  |  
我想找到第一行、第二行、第三行的总数,并在“总计”列中显示它们,所以我这样做了

SELECT sum(data1,data2) as database_value,sum(data3,data4) as database_not_value,sum(database_value+database_not_value) as total
  from table_name;

| ID |     science_name_short    |database_value   | database_not_value|Total | 
|  1 | Rhododendron phipli       |3                | 4                 |   7  |
|  2 | Rhododendron felica       |5                |6                  |   11 |
|3   | Rhododendron deron        |5                | 7                 |   12 |
|4   | Rhododendron  sednuns     |5                |8                  |   13 |



 then i get error as column "database_value" does not exist

不能在同一查询级别使用别名,若要获取总计,需要重复表达式

SELECT sum(data1 + data2) as database_value,
sum(data3 + data4) as database_not_value,
sum(data1 + data2) + sum(data3+ data4)  as total
from table_name;

sum也使用单参数,因此我假设您使用+而不是逗号添加数据集

此查询无法生成该结果,很明显,这不是您的“原始”数据See我不知道sum可以在MySQL中使用CSV参数列表。哦,等等,给我们一些像SQL小提琴一样的东西看看,也许我们能帮上忙..thnk u khalid: