SUM() and GROUP BY

Does this seem right?

druid=> SELECT COUNT(*) FROM acctrans;
count
-----
0
(1 row)

druid=> SELECT client_id, SUM(tramount) FROM acctrans GROUP BY client_id;
client_id|sum
---------+---
|
(1 row)

If there are no rows in the table then shouldn't the result be no rows
when GROUP BY is used? Further, What about this?

druid=> SELECT SUM(tramount) FROM acctrans;
sum
---

(1 row)

Shouldn't that be 0.00?

What will the NUMERIC or DECIMAL types do in these situations? It
looks like INTEGER has the same behaviour as MONEY (which tramount is.)

-- 
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