How to get count(*) total from DB2 with having clause? - db2

Question

How do I get the sum of all return rows with group by clause in DB2?
For example:
Desc Ctr
---- ---
Bowl 30
Plate 21
Spoon 6
Sum 57
SELECT COUNT (name) as Desc, Count(*) OVER ALL
GROUP BY name
Above query return error from DB2. What is the proper SQL statement to return SUM of all rows?
Thanks,
Brandon.

Answer 1

Try this query,
select name, count(*) from table group by name

Answer 2

What is your platform of Db2?
If you want just the total count of rows, then
select count(*)
from mytable
If you want the subtotals by name plus the total, SQL didn't originally support that. You had to union the two results.
select name, count(*) as cnt
from mytable
group by name
UNION ALL
select '', count(*)
from mytable
However more modern versions have added ROLLUP (and CUBE) functionality...
select name, count(*) as cnt
from mytable
group by name with rollup
Edit
To put a value for name, you could simply use COALESCE() assuming name won't ever be null except in the total row.
select coalesce(name,'-Total-') as name, count(*) as cnt
from mytable
group by name with rollup
The more correct method is to use the GROUPING() function
either return just the flag
select name, count(*) as cnt, grouping(name) as IS_TOTAL
from mytable
group by name with rollup
or use it to set the text
select case grouping(name)
when 1 then '-Total-'
else name
end as name
, count(*) as cnt
from mytable
group by name with rollup
Inculde total
To include the total on each line, you could do something like so...
with tot as (select count(*) as cnt from mytable)
select name
, count(*) as name_cnt
, tot.cnt as total_cnt
from mytable
cross join tot
group by name
Note that this will read mytable twice, once for the total and again for the detail rows. But it's real obvious what you're doing.
Another option would be something like so
with allrows as (
select name, count(*) as cnt, grouping(name) as IS_TOTAL
from mytable
group by name with rollup
)
select dtl.name, dtl.cnt, tot.cnt
from allrows dtl
join allrows tot
on tot.is_total = 1
where
dtl.is_total = 0