Amazon Redshift will no longer support the creation of new Python UDFs starting Patch 198. Existing Python UDFs will continue to function until June 30, 2026. For more information, see the [ blog post ](https://amazonaws-china.com/blogs/big-data/amazon-redshift-python-user-defined-functions-will-reach-end-of-support-after-june-30-2026/). 

# ROW\$1NUMBER window function
ROW\$1NUMBER

Assigns an ordinal number of the current row within a group of rows, counting from 1, based on the ORDER BY expression in the OVER clause. If the optional PARTITION BY clause is present, the ordinal numbers are reset for each group of rows. Rows with equal values for the ORDER BY expressions receive the different row numbers nondeterministically. 

## Syntax
Syntax

```
ROW_NUMBER() OVER(
  [ PARTITION BY expr_list ]
  [ ORDER BY order_list ]
)
```

## Arguments
Arguments

( )   
The function takes no arguments, but the empty parentheses are required. 

OVER   
The window function clause for the ROW\$1NUMBER function. 

PARTITION BY *expr\$1list*   
Optional. One or more column expressions that divide the results into sets of rows. 

ORDER BY *order\$1list*   
Optional. One or more column expressions that defines the order of rows within a set. If no PARTITION BY is specified, ORDER BY uses the entire table.   
If ORDER BY does not produce a unique ordering or is omitted, the order of the rows is nondeterministic. For more information, see [Unique ordering of data for window functions](c_Window_functions.md#r_Examples_order_by_WF). 

## Return type
Return type

BIGINT

## Examples
Examples

The following examples use the `WINSALES` table. For a description of the `WINSALES` table, see [Sample table for window function examples](c_Window_functions.md#r_Window_function_example). 

The following example orders the table by QTY (in ascending order), then assigns a row number to each row. The results are sorted after the window function results are applied. 

```
SELECT salesid, sellerid, qty, 
ROW_NUMBER() OVER(
   ORDER BY qty ASC) AS row
FROM winsales
ORDER BY 4,1;

salesid   sellerid   qty   row
---------+----------+-----+-----
   30001 |        3 |  10 |   1	
   10001 |        1 |  10 |   2	
   10006 |        1 |  10 |   3
   40005 |        4 |  10 |   4
   30003 |        3 |  15 |   5
   20001 |        2 |  20 |   6
   20002 |        2 |  20 |   7
   30004 |        3 |  20 |   8
   10005 |        1 |  30 |   9
   30007 |        3 |  30 |  10
   40001 |        4 |  40 |  11
```

The following example partitions the table by SELLERID and orders each partition by QTY (in ascending order), then assigns a row number to each row. The results are sorted after the window function results are applied. 

```
SELECT salesid, sellerid, qty, 
ROW_NUMBER() OVER(
  PARTITION BY sellerid
  ORDER BY qty ASC) AS row_by_seller
FROM winsales
ORDER BY 2,4;

 salesid | sellerid | qty | row_by_seller
---------+----------+-----+-----
   10001 |        1 |  10 |   1
   10006 |        1 |  10 |   2
   10005 |        1 |  30 |   3
   20001 |        2 |  20 |   1
   20002 |        2 |  20 |   2
   30001 |        3 |  10 |   1
   30003 |        3 |  15 |   2
   30004 |        3 |  20 |   3
   30007 |        3 |  30 |   4
   40005 |        4 |  10 |   1
   40001 |        4 |  40 |   2
```

The following example shows the results when not using the optional clauses. 

```
SELECT salesid, sellerid, qty, ROW_NUMBER() OVER() AS row
FROM winsales
ORDER BY 4,1;

salesid   sellerid   qty   row
---------+----------+-----+-----
   30001 |        3 |  10 |   1	
   10001 |        1 |  10 |   2	
   10005 |        1 |  30 |   3
   40001 |        4 |  40 |   4
   10006 |        1 |  10 |   5
   20001 |        2 |  20 |   6
   40005 |        4 |  10 |   7
   20002 |        2 |  20 |   8
   30003 |        3 |  15 |   9
   30004 |        3 |  20 |  10
   30007 |        3 |  30 |  11
```