Snowflake中含WHERE...CONNECT BY的EXISTS子查询不支持问题咨询

运行以下代码时，我遇到错误 "Unsupported subquery type cannot be evaluated"：

SELECT '"' || TABLE_CATALOG || '"."' || TABLE_SCHEMA || '"."' || NAME || '"'
FROM SNOWFLAKE.ACCOUNT_USAGE.GRANTS_TO_ROLES TBL_LIST
WHERE DELETED_ON IS NULL
    AND GRANTED_ON = 'TABLE'
    AND PRIVILEGE IN ('SELECT','DELETE')
    AND EXISTS (SELECT 1
                FROM (SELECT DISTINCT NAME AS CHILD, GRANTEE_NAME AS PARENT
                        FROM SNOWFLAKE.ACCOUNT_USAGE.GRANTS_TO_ROLES
                        WHERE GRANTED_ON = 'ROLE'
                            AND DELETED_ON IS NULL)
                WHERE GRANTEE_NAME IN (CHILD, CURRENT_ROLE())
                START WITH PARENT = CURRENT_ROLE()
                CONNECT BY PARENT = PRIOR CHILD)
GROUP BY '"' || TABLE_CATALOG || '"."' || TABLE_SCHEMA || '"."' || NAME || '"'
HAVING COUNT(DISTINCT PRIVILEGE) = 2;

这段代码的目标是获取当前角色同时拥有SELECT和DELETE权限的所有表列表。我在Snowflake中创建了最小复现示例：

SELECT *
FROM SNOWFLAKE.ACCOUNT_USAGE.GRANTS_TO_ROLES TBL_LIST
WHERE EXISTS (SELECT 1
                FROM (SELECT DISTINCT NAME AS CHILD, GRANTEE_NAME AS PARENT
                        FROM SNOWFLAKE.ACCOUNT_USAGE.GRANTS_TO_ROLES)
                WHERE GRANTEE_NAME = CHILD
                START WITH PARENT = CURRENT_ROLE()
                CONNECT BY PARENT = PRIOR CHILD);

我已经确认：移除嵌套的WHERE子句，或者去掉START WITH...CONNECT BY递归查询序列后，查询就能正常执行。我想了解这类子查询不被支持的原因。

更新（6个月后）：我遇到了未使用CONNECT BY的类似问题。

内容的提问来源于stack exchange，提问作者DisasterArea