将SQL SUM从联合转换为JPQL

Hi-im使用EclipseLink，需要将follow sql查询转换为JPQL

SELECT sum(subtotais.peso) FROM 
(
    SELECT SUM(t1.peso) as peso
    FROM table1 t1
    WHERE t1.arg1 = 1 AND t1.arg4 = 2 AND t1.arg3 = 1
    UNION
    SELECT SUM(cli.peso) as peso        
    FROM table1 t2
    WHERE t2.arg1 = 1 AND t2.arg2 = 2 AND t2.arg3 = 0
) subtotais;

我试过这个

SELECT SUM(subtotais.peso) FROM 
(
    SELECT SUM(t1.peso) AS peso
    FROM Table1 t1
    WHERE t1.arg1 = 1 AND t1.arg4 = 2
    AND t1.arg3 = true

    UNION

    SELECT SUM(cli2.peso) AS peso 
    FROM Table2 t2 
    WHERE t2.arg1 = 1 AND t2.arg2 = 2 
    AND t2.arg3 = false
) subtotais;

我犯了以下错误： [200200]子表达式中缺少右括号。 [201，201]必须为范围变量声明提供标识变量。 [392，404]表达式无效，这意味着它不遵循JPQL语法。

---

[404408]查询包含格式不正确的结尾。

我知道jpa不支持UNION，那么我如何从UNION中退出？为什么需要UNION？如果两个总数相等，则只返回一个。这就是你真正需要的吗？