函数date_format(timestamp without time zone,unknow)不存在，没有匹配指定名称和参数类型的函数，您也许需要增加明确的类型转换
瀚高库报错：
CREATE OR REPLACE FUNCTION date_format(indate TIMESTAMP, intext text)
RETURNS text
LANGUAGE plpgsql
AS $function$
BEGIN
IF upper(inText) = upper('%Y%m%d_%H%i') THEN
return to_char(inDate,'YYYYMMDD_HH24MI');
END IF;
IF upper(inText) = upper('%Y%m%d%H%i%s') THEN
return to_char(inDate,'YYYYMMDDHH24MISS');
END IF;
IF upper(inText) = upper('%Y-%m-%d %H') THEN
return to_char(inDate,'YYYY-MM-DD HH24');
END IF;
IF upper(inText) = upper('%y%m%d') THEN
return to_char(inDate,'YYYYMMDD');
END IF;
IF upper(inText) = upper('%Y-%m') THEN
return to_char(inDate,'YYYY-MM');
end if;
IF upper(inText) = upper('%m%d') THEN
return to_char(inDate,'MMDD');
END IF;
IF upper(inText) = upper('%Y-%m-%d %H:%i:%s') THEN
return to_char(inDate,'YYYY-MM-DD HH24:MI:SS');
END IF;
return '';
END;
$function$
