SQL Server/T-SQL/Aggregate Functions/COUNT BIG

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COUNT_BIG deals with NULL values

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary bigint, 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", NULL, "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", NULL, "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                      NULL 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary                       NULL 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> 3> --. 4> select COUNT_BIG(salary) from employee 5> GO 

                  7

Warning: Null value is eliminated by an aggregate or other SET operation. 1> 2> 3> 4> drop table employee 5> GO 1> 

      </source>


COUNT_BIG: return value has a data type of bigint

   <source lang="sql">

1> create table employee( 2> ID int, 3> name nvarchar (10), 4> salary bigint, 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> 3> --COUNT_BIG: return value has a data type of bigint 4> 5> select COUNT_BIG(DISTINCT salary) from employee 6> GO 

                  9

(1 rows affected) 1> 2> 3> 4> drop table employee 5> GO 1> 

      </source>
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