SQL Server/T-SQL/Select Query/Group BY

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Combine MAX function with group by

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> SELECT City, MIN(Salary),MAX(Salary) 3> FROM Employee 4> WHERE ID BETWEEN 1 AND 10 5> GROUP BY City 6> GO City


----------- -----------

New York 40420 90620 Toronto 24020 70060 Vancouver 14420 80026 (3 rows affected) 1> 2> 3> 4> 5> 6> drop table employee 7> GO 1>

      </source>
   
  


Combine MIN function with group by

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> SELECT City, MIN(Salary),MAX(Salary) 3> FROM Employee 4> WHERE ID BETWEEN 1 AND 10 5> GROUP BY City 6> GO City


----------- -----------

New York 40420 90620 Toronto 24020 70060 Vancouver 14420 80026 (3 rows affected) 1> 2> 3> 4> 5> 6> drop table employee 7> GO 1>

      </source>
   
  


Count() and Sum() with group by and column alias

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> SELECT City 3> , SUM(Salary) As QtySum 4> , COUNT(salary) As DetailCount 5> FROM Employee 6> GROUP BY City 7> GO City QtySum DetailCount


----------- -----------

New York 171660 3 Toronto 154100 3 Vancouver 120466 3 (3 rows affected) 1> 2> drop table employee 3> GO 1>

      </source>
   
  


Count with "group by"

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> SELECT City, COUNT(*) "Employees" 3> FROM Employee 4> GROUP BY City 5> GO City Employees


-----------

New York 3 Toronto 3 Vancouver 3 (3 rows affected) 1> 2> 3> drop table employee 4> GO 1>

      </source>
   
  


GROUP BY builds different groups for all possible values (NULL, too!)

   <source lang="sql">

1> 2> CREATE TABLE works_on (emp_no INTEGER NOT NULL, 3> project_no CHAR(4) NOT NULL, 4> job CHAR (15) NULL, 5> enter_date DATETIME NULL) 6> 7> insert into works_on values (1, "p1", "analyst", "1997.10.1") 8> insert into works_on values (1, "p3", "manager", "1999.1.1") 9> insert into works_on values (2, "p2", "clerk", "1998.2.15") 10> insert into works_on values (2, "p2", NULL, "1998.6.1") 11> insert into works_on values (3, "p2", NULL, "1997.12.15") 12> insert into works_on values (4, "p3", "analyst", "1998.10.15") 13> insert into works_on values (5, "p1", "manager", "1998.4.15") 14> insert into works_on values (6, "p1", NULL, "1998.8.1") 15> insert into works_on values (7, "p2", "clerk", "1999.2.1") 16> insert into works_on values (8, "p3", "clerk", "1997.11.15") 17> insert into works_on values (7, "p1", "clerk", "1998.1.4") 18> GO (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) (1 rows affected) 1> 2> -- GROUP BY builds different groups for all possible values (NULL, too!) 3> 4> SELECT project_no, job FROM works_on GROUP BY project_no, job 5> GO project_no job


---------------

p1 NULL p1 analyst p1 clerk p1 manager p2 NULL p2 clerk p3 analyst p3 clerk p3 manager (9 rows affected) 1> 2> drop table works_on 3> GO 1>

      </source>
   
  


GROUP BY clause with an aggregator "SUM()"

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> --GROUP BY clause with an aggregator "SUM()". 3> 4> SELECT region, SUM(Salary) 5> FROM Employee 6> WHERE ID BETWEEN 1 AND 10 7> GROUP BY Region 8> GO region


-----------

N 151120 W 295106 (2 rows affected) 1> 2> 3> drop table employee 4> GO 1>

      </source>
   
  


Simple "group by" demo

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> SELECT Name 3> FROM Employee 4> GROUP BY Name 5> GO Name


Alison Celia Chris David James Jason Linda Mary Robert (9 rows affected) 1> 2> drop table employee 3> GO 1>

      </source>
   
  


Subquery as one column

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> create table job( 3> ID int, 4> title nvarchar (10), 5> averageSalary int) 6> GO 1> 2> 3> 4> insert into job(ID, title, averageSalary) values(1,"Developer",3000) 5> GO (1 rows affected) 1> insert into job(ID, title, averageSalary) values(2,"Tester", 4000) 2> GO (1 rows affected) 1> insert into job(ID, title, averageSalary) values(3,"Designer", 5000) 2> GO (1 rows affected) 1> insert into job(ID, title, averageSalary) values(4,"Programmer", 6000) 2> GO (1 rows affected) 1> 2> select * from job 3> GO ID title averageSalary


---------- -------------
         1 Developer           3000
         2 Tester              4000
         3 Designer            5000
         4 Programmer          6000

(4 rows affected) 1> 2> SELECT ID 3> , (SELECT Title FROM job 4> WHERE Employee.ID = Job.ID) 5> AS Title 6> FROM Employee 7> GO ID Title


----------
         1 Developer
         2 Tester
         3 Designer
         4 Programmer
         5 NULL
         6 NULL
         7 NULL
         8 NULL
         9 NULL

(9 rows affected) 1> 2> drop table employee 3> GO

      </source>
   
  


When grouping on more than one column, every unique combination of grouped values produces a row in the result set

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary int, 5> start_date datetime, 6> city nvarchar (10), 7> region char (1)) 8> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> -- When grouping on more than one column, every unique combination of grouped values produces a row in the result set. 3> 4> SELECT City 5> , Region 6> FROM Employee 7> GROUP BY City, Region 8> ORDER BY City, Region 9> GO City Region


------

New York N New York W Toronto N Toronto W Vancouver N Vancouver W (6 rows affected) 1> 2> 3> drop table employee 4> GO 1>

      </source>