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

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RANK() OVER

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>


Returning Rows by Rank Without Gaps

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


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

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)