SQL Server RAND() Function

Definition and Usage

The RAND() function in SQL Server generates a pseudo-random floating-point number between 0 (inclusive) and 1 (exclusive). Whether it produces truly random numbers or a repeatable sequence depends on whether a seed value is provided.

Syntax

Syntax

RAND ( seed )

Parameter Values

Parameter Description
seed Optional. An integer value used as a seed. If provided, RAND() will generate the same sequence of random numbers each time it's called with that seed. If omitted, a different random number is generated each time.

Examples

Example 1: Generating a Random Number (No Seed)

This example demonstrates generating a random decimal number between 0 and 1 without using a seed value.

SQL Query

SELECT RAND();
Output

-- Output will vary. Example:
--  Column1
--  -----------
--  0.73654987

Example 2: Generating a Random Number (With Seed)

This example uses a seed value (6) to generate a repeatable sequence of random numbers.

SQL Query

SELECT RAND(6);
Output

-- Output will be the same every time with seed 6. Example:
--  Column1
--  -----------
--  0.417022

Example 3: Generating a Random Number within a Range (5 to 10, exclusive of 10)

This example demonstrates how to generate random numbers within a specific range (5 to 10, excluding 10).

SQL Query

SELECT RAND()*(10-5)+5;
Output

-- Output will vary, but always between 5 and 10 (exclusive of 10). Example:
--  Column1
--  -----------
--  7.283749

Example 4: Generating a Random Integer within a Range (5 to 10, inclusive)

This example generates random integers between 5 and 10 (inclusive).

SQL Query

SELECT FLOOR(RAND()*(10-5+1)+5);
Output

-- Output will vary, but always an integer between 5 and 10 (inclusive). Example:
--  Column1
--  -----------
--  8

Technical Details

The RAND() function is available in SQL Server 2008 and later, Azure SQL Database, and Azure SQL Data Warehouse.