UNION on two select gives 'SQL Error: ORA-00907: missing right parenthesis'

Question

I'm trying to UNION the results of two queries. But I'm getting the following error:

Error at Command Line:9 Column:81
Error report:
SQL Error: ORA-00907: missing right parenthesis
00907. 00000 -  "missing right parenthesis"

Here's my query:

SELECT application_id, clicks, datee, client_id FROM(
(select 
    APPL_CD AS application_id, 
    count(*) as clicks, 
    to_date((to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy')), 'dd-mm-yyyy') as datee, 
    ALRT_RSPNS_FROM_CLIENT_ID AS client_id 
from  ALRT_PLATFORM_ALRT_HSTRY
    where  ACTN_TAKE_CD is not null 
    group by to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy'), APPL_CD, ALRT_RSPNS_FROM_CLIENT_ID order by datee) 
UNION ALL
(select 
    APPL_CD AS application_id, 
    count(*) as clicks, 
    to_date((to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy')), 'dd-mm-yyyy') as datee, 
    ALRT_RSPNS_FROM_CLIENT_ID AS client_id 
from  ALRT_PLATFORM_ALRT
    where  ACTN_TAKE_CD is not null 
    group by to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy'), APPL_CD, ALRT_RSPNS_FROM_CLIENT_ID order by datee )
)

Answer 1

Remove the ORDER BY from the nested queries:

SELECT application_id, clicks, datee, client_id FROM(
(select 
    APPL_CD AS application_id, 
    count(*) as clicks, 
    to_date((to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy')), 'dd-mm-yyyy') as datee, 
    ALRT_RSPNS_FROM_CLIENT_ID AS client_id 
from  ALRT_PLATFORM_ALRT_HSTRY
    where  ACTN_TAKE_CD is not null 
    group by to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy'), APPL_CD, ALRT_RSPNS_FROM_CLIENT_ID) 
UNION ALL
(select 
    APPL_CD AS application_id, 
    count(*) as clicks, 
    to_date((to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy')), 'dd-mm-yyyy') as datee, 
    ALRT_RSPNS_FROM_CLIENT_ID AS client_id 
from  ALRT_PLATFORM_ALRT
    where  ACTN_TAKE_CD is not null 
    group by to_char(ACTN_TAKE_DATA_TM, 'dd-mm-yyyy'), APPL_CD, ALRT_RSPNS_FROM_CLIENT_ID )
)