RANK

Returns an ascending sequence of integers, starting with 1. The output sequence produces duplicate integers for duplicate values of the ORDER BY expressions. After generating duplicate output values for the tied input values, the function increments the sequence by the number of tied values. Therefore, the sequence contains both duplicates and gaps when the input contains duplicates. Starts the sequence over for each group produced by the PARTITIONED BY clause.

Syntax:

RANK() OVER([partition_by_clause] order_by_clause)

The PARTITION BY clause is optional. The ORDER BY clause is required. The window clause is not allowed.

Usage notes:

Often used for top-N and bottom-N queries. For example, it could produce a top 10 report including several items that were tied for 10th place.

Similar to ROW_NUMBER and DENSE_RANK. These functions differ in how they treat duplicate combinations of values.

Examples:

The following example demonstrates how the RANK() function identifies where each value places in the result set, producing the same result for duplicate values, and skipping values in the sequence to account for the number of duplicates. For example, when results are ordered by the X column, both 1 values are tied for first; both 2 values are tied for third; and so on.

select x, rank() over(order by x) as rank, property from int_t;
+----+------+----------+
| x  | rank | property |
+----+------+----------+
| 1  | 1    | square   |
| 1  | 1    | odd      |
| 2  | 3    | even     |
| 2  | 3    | prime    |
| 3  | 5    | prime    |
| 3  | 5    | odd      |
| 4  | 7    | even     |
| 4  | 7    | square   |
| 5  | 9    | odd      |
| 5  | 9    | prime    |
| 6  | 11   | even     |
| 6  | 11   | perfect  |
| 7  | 13   | lucky    |
| 7  | 13   | lucky    |
| 7  | 13   | lucky    |
| 7  | 13   | odd      |
| 7  | 13   | prime    |
| 8  | 18   | even     |
| 9  | 19   | square   |
| 9  | 19   | odd      |
| 10 | 21   | round    |
| 10 | 21   | even     |
+----+------+----------+

The following examples show how the RANK() function is affected by the PARTITION property within the ORDER BY clause.

Partitioning by the PROPERTY column groups all the even, odd, and so on values together, and RANK() returns the place of each value within the group, producing several ascending sequences.

select x, rank() over(partition by property order by x) as rank, property from int_t;
+----+------+----------+
| x  | rank | property |
+----+------+----------+
| 2  | 1    | even     |
| 4  | 2    | even     |
| 6  | 3    | even     |
| 8  | 4    | even     |
| 10 | 5    | even     |
| 7  | 1    | lucky    |
| 7  | 1    | lucky    |
| 7  | 1    | lucky    |
| 1  | 1    | odd      |
| 3  | 2    | odd      |
| 5  | 3    | odd      |
| 7  | 4    | odd      |
| 9  | 5    | odd      |
| 6  | 1    | perfect  |
| 2  | 1    | prime    |
| 3  | 2    | prime    |
| 5  | 3    | prime    |
| 7  | 4    | prime    |
| 10 | 1    | round    |
| 1  | 1    | square   |
| 4  | 2    | square   |
| 9  | 3    | square   |
+----+------+----------+

Partitioning by the X column groups all the duplicate numbers together and returns the place each value within the group; because each value occurs only 1 or 2 times, RANK() designates each X value as either first or second within its group.

select x, rank() over(partition by x order by property) as rank, property from int_t;
+----+------+----------+
| x  | rank | property |
+----+------+----------+
| 1  | 1    | odd      |
| 1  | 2    | square   |
| 2  | 1    | even     |
| 2  | 2    | prime    |
| 3  | 1    | odd      |
| 3  | 2    | prime    |
| 4  | 1    | even     |
| 4  | 2    | square   |
| 5  | 1    | odd      |
| 5  | 2    | prime    |
| 6  | 1    | even     |
| 6  | 2    | perfect  |
| 7  | 1    | lucky    |
| 7  | 1    | lucky    |
| 7  | 1    | lucky    |
| 7  | 4    | odd      |
| 7  | 5    | prime    |
| 8  | 1    | even     |
| 9  | 1    | odd      |
| 9  | 2    | square   |
| 10 | 1    | even     |
| 10 | 2    | round    |
+----+------+----------+

The following example shows how a magazine might prepare a list of history's wealthiest people. Croesus and Midas are tied for second, then Crassus is fourth.

select rank() over (order by net_worth desc) as rank, name, net_worth from wealth order by rank, name;
+------+---------+---------------+
| rank | name    | net_worth     |
+------+---------+---------------+
| 1    | Solomon | 2000000000.00 |
| 2    | Croesus | 1000000000.00 |
| 2    | Midas   | 1000000000.00 |
| 4    | Crassus | 500000000.00  |
| 5    | Scrooge | 80000000.00   |
+------+---------+---------------+