Allows you to set conditions on the groups returned by the GROUP BY clause. If the HAVING clause is used without the GROUP BY clause, the implicit group against which the search condition is evaluated is all the rows returned by the WHERE clause.
Syntax
HAVING search_condition
Notes
A condition of the HAVING clause can compare one aggregate function value with another aggregate function value or a constant.
Example
The HAVING clause in the following example compares the value of an aggregate function
(COUNT (*)) to a constant (10):
SELECT CustNum, COUNT(*)
FROM Order
WHERE OrderDate < TO_DATE ('3/31/2004')
GROUP BY CustNum
HAVING COUNT (*) > 10 ;
The query returns the customer number and number of orders for all customers who had more than 10 orders before March 31.
