SQL Server error selecting count on a subquery - sql-server-2005

Question

I am trying to select the count of the number of rows returned on a query. The query is
Select
a.itm_cd, max(b.doc_num) ,max(c.text)
from
ist b, itm_trn a, ist_cmnt c
where
a.ist_seq_num = b.ist_seq_num
and a.ist_seq_num = c.ist_seq_num
and a.ist_wr_dt = b.ist_wr_dt
and a.new_loc_cd like 'BOX115'
and a.ITT_CD = 'XFR' and a.create_dt >'21-AUG-16'
group by
a.itm_cd;
For this particular query I return 3 rows, I need to write a query that returns how many rows are returned.
I have tried this :
Select
count(*)
from
(Select
a.itm_cd, max(b.doc_num), max(c.text)
from
ist b,itm_trn a, ist_cmnt c
where
a.ist_seq_num = b.ist_seq_num
and a.ist_seq_num = c.ist_seq_num
and a.ist_wr_dt = b.ist_wr_dt
and a.new_loc_cd like 'BOX115'
and a.ITT_CD = 'XFR'
and a.create_dt > '21-AUG-16'
group by
a.itm_cd);
This results in a syntax error
Msg 102, level 15, state 1 line 1
Incorrect syntax near ')'.
I am not sure what I am doing wrong, I have a similar SQL statement that works this way in Oracle, but have not found where I am messing up in SQL Server.
UPDATE:
as per the first suggestion I received I tried :
Select
count(*)
from
(Select
a.itm_cd, max(b.doc_num), max(c.text)
from
ist b, itm_trn a, ist_cmnt c
where
a.ist_seq_num = b.ist_seq_num
and a.ist_seq_num = c.ist_seq_num
and a.ist_wr_dt = b.ist_wr_dt
and a.new_loc_cd like 'BOX115'
and a.ITT_CD = 'XFR'
and a.create_dt > '21-AUG-16'
group by
a.itm_cd) as T
The errors returned were
Msg 8155, Level 16, State 2, Line 12
No column was specified for column 2 of 'T'.
Msg 8155, Level 16, State 2, Line 12
No column was specified for column 3 of 'T'.

Answer 1

AS per the error message, you should add alias name for your aggregated columns. Try like this,
SELECT count(*)
FROM (
SELECT a.itm_cd
,max(b.doc_num) AS MaxDoc_num
,max(c.TEXT) AS MaxText
FROM ist b
,itm_trn a
,ist_cmnt c
WHERE a.ist_seq_num = b.ist_seq_num
AND a.ist_seq_num = c.ist_seq_num
AND a.ist_wr_dt = b.ist_wr_dt
AND a.new_loc_cd LIKE 'BOX115'
AND a.ITT_CD = 'XFR'
AND a.create_dt > '21-AUG-16'
GROUP BY a.itm_cd
) T
You can easily find the count using this query.
SELECT count(DISTINCT a.itm_cd)
FROM ist b
,itm_trn a
,ist_cmnt c
WHERE a.ist_seq_num = b.ist_seq_num
AND a.ist_seq_num = c.ist_seq_num
AND a.ist_wr_dt = b.ist_wr_dt
AND a.new_loc_cd LIKE 'BOX115'
AND a.ITT_CD = 'XFR'
AND a.create_dt > '21-AUG-16'