The HAVING clause has the same meaning to groups of rows that the WHERE clause has to each individual row.
The syntax of the HAVING clause is
HAVING condition
where condition contains aggregate functions or constants.
9>
10>
11> CREATE TABLE employee(
12> id INTEGER NOT NULL PRIMARY KEY,
13> first_name VARCHAR(10),
14> last_name VARCHAR(10),
15> salary DECIMAL(10,2),
16> start_Date DATETIME,
17> region VARCHAR(10),
18> city VARCHAR(20),
19> managerid INTEGER
20> );
21> GO
1> INSERT INTO employee VALUES (1, 'Jason' , 'Martin', 5890,'2005-03-22','North','Vancouver',3);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (2, 'Alison', 'Mathews',4789,'2003-07-21','South','Utown',4);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (3, 'James' , 'Smith', 6678,'2001-12-01','North','Paris',5);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (4, 'Celia' , 'Rice', 5567,'2006-03-03','South','London',6);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (5, 'Robert', 'Black', 4467,'2004-07-02','East','Newton',7);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (6, 'Linda' , 'Green' , 6456,'2002-05-19','East','Calgary',8);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (7, 'David' , 'Larry', 5345,'2008-03-18','West','New York',9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (8, 'James' , 'Cat', 4234,'2007-07-17','West','Regina',9);
2> GO
(1 rows affected)
1> INSERT INTO employee VALUES (9, 'Joan' , 'Act', 6123,'2001-04-16','North','Toronto',10);
2> GO
(1 rows affected)
1>
2> select * from employee;
3> GO
id first_name last_name salary start_Date region city managerid
----------- ---------- ---------- ------------ ----------------------- ---------- -------------------- -----------
1 Jason Martin 5890.00 2005-03-22 00:00:00.000 North Vancouver 3
2 Alison Mathews 4789.00 2003-07-21 00:00:00.000 South Utown 4
3 James Smith 6678.00 2001-12-01 00:00:00.000 North Paris 5
4 Celia Rice 5567.00 2006-03-03 00:00:00.000 South London 6
5 Robert Black 4467.00 2004-07-02 00:00:00.000 East Newton 7
6 Linda Green 6456.00 2002-05-19 00:00:00.000 East Calgary 8
7 David Larry 5345.00 2008-03-18 00:00:00.000 West New York 9
8 James Cat 4234.00 2007-07-17 00:00:00.000 West Regina 9
9 Joan Act 6123.00 2001-04-16 00:00:00.000 North Toronto 10
(9 rows affected)
1>
2>
3> SELECT region
4> FROM employee
5> GROUP BY region
6> HAVING COUNT(*) < 3
7> GO
region
----------
East
South
West
(3 rows affected)
1> drop table employee;
2> GO