在别名中使用SUM - use SUM in alias

use SUM in alias

本文关键字：SUM 别名 | 更新日期: 2023-09-27

我想在别名中使用SUM函数请看下面的代码，我希望你能理解：

     SELECT PATIENTS.NAME,
       PATIENTS.FAMILY,
       COST.COST,
       COST.REALDATEYEAR,
       COST.REALDATEMONTH,
       COST.REALDATEDAY,
       CONTRACTS.ID,
       CONTRACTS.FRANSHIZ AS CO1,
       PATIENTS.COMPANY,
       CONTRACTS.COMPANY,
       COST.TYPE,
       TARRIFS.ID,
       TARRIFS.ACTION,
       TARRIFS.COST       AS CO
  FROM PATIENTS
 INNER JOIN COST
 INNER JOIN CONTRACTS
 INNER JOIN TARRIFS
    ON PATIENTS.SINGLE_ID = COST.SINGLE_ID
   AND COST.TYPE = TARRIFS.ID
   AND CONTRACTS.ID = PATIENTS.COMPANY

我想对co1和co使用SUM，

使用SUM时需要使用GROUP BY。

你的查询是这样的。

SELECT PATIENTS.NAME,
       PATIENTS.FAMILY,
       COST.COST,
       COST.REALDATEYEAR,
       COST.REALDATEMONTH,
       COST.REALDATEDAY,
       CONTRACTS.ID,
       SUM(CONTRACTS.FRANSHIZ) AS CO1,
       PATIENTS.COMPANY,
       CONTRACTS.COMPANY,
       COST.TYPE,
       TARRIFS.ID,
       TARRIFS.ACTION,
       TARRIFS.COST AS CO
  FROM PATIENTS
 INNER JOIN COST
 INNER JOIN CONTRACTS
 INNER JOIN TARRIFS
    ON PATIENTS.SINGLE_ID = COST.SINGLE_ID
   AND COST.TYPE = TARRIFS.ID
   AND CONTRACTS.ID = PATIENTS.COMPANY
 GROUP BY CONTRACTS.FRANSHIZ