【达梦8】自定义函数创建的对象带有编译错误，原MySQL自定义函数转入达梦8

自定义函数创建的对象带有编译错误，原MySQL自定义函数转入达梦8
原MySQL函数如下：
CREATE DEFINER=external@% FUNCTION getChildrenOrganList(rootId VARCHAR ( 1000 )) RETURNS varchar(1000) CHARSET utf8mb4 COLLATE utf8mb4_german2_ci
BEGIN
DECLARE
sTemp VARCHAR ( 1000 );
DECLARE
sTempChd VARCHAR ( 1000 );

SET sTemp = '';
SET sTempChd = cast( rootId AS CHAR );

WHILE sTempChd IS NOT NULL DO
SET sTemp = concat( sTemp, ',', sTempChd );
SELECT
group_concat( F_Id ) INTO sTempChd
FROM
base_organize
WHERE
FIND_IN_SET( F_ParentId, sTempChd )> 0;
END WHILE;
RETURN sTemp;
复制
END

我修改并执行的达梦函数如下：
CREATE OR REPLACE FUNCTION getChildrenOrganList(rootId IN VARCHAR(1000))
RETURN VARCHAR(1000)
AS
sTemp VARCHAR(1000);
BEGIN
sTemp := ‘’;
sTempChd := cast( rootId AS VARCHAR(1000));
WHILE sTempChd IS NOT NULL
LOOP
sTemp :=CONCAT( sTemp, ‘,’, sTempChd );
SELECT
wm_concat( F_Id ) as sTempChd
FROM
base_organize
WHERE
FIND_IN_SET(F_ParentId,sTempChd) > 0;
END LOOP;
RETURN sTemp;
END;

我修改完之后提示：自定义函数创建的对象带有编译错误，但没有其他附属信息，请问这个MySQL自定义函数应该如何修改成达梦的自定义函数