SQL Server/T-SQL Tutorial/Aggregate Functions/RANK

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RANK() OVER

   <source lang="sql">

5> create table department( 6> dept_name char(20) not null, 7> emp_cnt int not null, 8> budget float, 9> date_month datetime); 10> GO 1> 2> insert into department values("Research", 5, 50000, "01.01.2002"); 3> insert into department values("Research", 10, 70000, "01.02.2002"); 4> insert into department values("Research", 5, 65000, "01.07.2002"); 5> insert into department values("Accounting", 5, 10000, "01.07.2002"); 6> insert into department values("Accounting", 10, 40000, "01.02.2002"); 7> insert into department values("Accounting", 6, 30000, "01.01.2002"); 8> insert into department values("Accounting", 6, 40000, "01.02.2003"); 9> insert into department values("Marketing", 6, 10000, "01.01.2003"); 10> insert into department values("Marketing", 10, 40000, "01.02.2003"); 11> insert into department values("Marketing", 3, 30000, "01.07.2003"); 12> insert into department values("Marketing", 5, 40000, "01.01.2003"); 13> 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> SELECT RANK() OVER(ORDER BY budget DESC) AS rank_budget,dept_name, emp_cnt, budget 3> FROM department 4> WHERE budget <= 50000; 5> GO rank_budget dept_name emp_cnt budget


-------------------- ----------- ------------------------
                  1 Research                       5                    50000
                  2 Accounting                    10                    40000
                  2 Accounting                     6                    40000
                  2 Marketing                     10                    40000
                  2 Marketing                      5                    40000
                  6 Marketing                      3                    30000
                  6 Accounting                     6                    30000
                  8 Accounting                     5                    10000
                  8 Marketing                      6                    10000

(9 rows affected) 1> drop table department; 2> GO 1> 2> 3></source>


Returning Rows by Rank Without Gaps

   <source lang="sql">

4> 5> CREATE TABLE employee( 6> id INTEGER NOT NULL PRIMARY KEY, 7> first_name VARCHAR(10), 8> last_name VARCHAR(10), 9> salary DECIMAL(10,2), 10> start_Date DATETIME, 11> region VARCHAR(10), 12> city VARCHAR(20), 13> managerid INTEGER 14> ); 15> 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> 4> SELECT ID,Salary, 5> DENSE_RANK() OVER (ORDER BY Salary DESC) as DENSE_RANK 6> FROM Employee 7> GO ID Salary DENSE_RANK


------------ --------------------
         3      6678.00                    1
         6      6456.00                    2
         9      6123.00                    3
         1      5890.00                    4
         4      5567.00                    5
         7      5345.00                    6
         2      4789.00                    7
         5      4467.00                    8
         8      4234.00                    9

(9 rows affected) 1> 2> drop table employee; 3> GO</source>


The RANK() function preserves the ordinal position of the row in the list.

   <source lang="sql">

RANK function increments its value for each row in the set. The syntax for RANK is as follows: RANK ( ) OVER ( [ < partition_by_clause > ] < order_by_clause > ) If rows with tied values exist, they will receive the same rank value For each duplicate value, the RANK() function skips the subsequent value so that the next non-duplicate value remains in its rightful position. 7> 8> CREATE TABLE employee( 9> id INTEGER NOT NULL PRIMARY KEY, 10> first_name VARCHAR(10), 11> last_name VARCHAR(10), 12> salary DECIMAL(10,2), 13> start_Date DATETIME, 14> region VARCHAR(10), 15> city VARCHAR(20), 16> managerid INTEGER 17> ); 18> GO 1> INSERT INTO employee VALUES (1, "Jason" , "Martin", 5890,"2005-03-22","North","Vancouver",3); 2> GO 1> INSERT INTO employee VALUES (2, "Alison", "Mathews",4789,"2003-07-21","South","Utown",4); 2> GO 1> INSERT INTO employee VALUES (3, "James" , "Smith", 6678,"2001-12-01","North","Paris",5); 2> GO 1> INSERT INTO employee VALUES (4, "Celia" , "Rice", 5567,"2006-03-03","South","London",6); 2> GO 1> INSERT INTO employee VALUES (5, "Robert", "Black", 4467,"2004-07-02","East","Newton",7); 2> GO 1> INSERT INTO employee VALUES (6, "Linda" , "Green" , 6456,"2002-05-19","East","Calgary",8); 2> GO 1> INSERT INTO employee VALUES (7, "David" , "Larry", 5345,"2008-03-18","West","New York",9); 2> GO 1> INSERT INTO employee VALUES (8, "James" , "Cat", 4234,"2007-07-17","West","Regina",9); 2> GO 1> INSERT INTO employee VALUES (9, "Joan" , "Act", 6123,"2001-04-16","North","Toronto",10); 2> GO 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 4> ID 5> , First_Name 6> , RANK() Over (ORDER BY First_Name) As Rank 7> FROM Employee 8> ORDER BY First_Name 9> 10> 11> drop table employee; 12> GO ID First_Name Rank


---------- --------------------
         2 Alison                        1
         4 Celia                         2
         7 David                         3
         8 James                         4
         3 James                         4
         1 Jason                         6
         9 Joan                          7
         6 Linda                         8
         5 Robert                        9

(9 rows affected)</source>