seed

Is an integer expression (tinyint, smallint, or int) that gives the seed value. If seed is not specified, the Microsoft SQL Server Database Engine assigns a seed value at random. For a specified seed value, the result returned is always the same.

float

Repetitive calls of RAND() with the same seed value return the same results.

For one connection, if RAND() is called with a specified seed value, all subsequent calls of RAND() produce results based on the seeded RAND() call. For example, the following query will always return the same sequence of numbers.

SELECT RAND(100), RAND(), RAND() 

The following example produces four different random numbers that are generated by the RAND function.

DECLARE @counter smallint;
SET @counter = 1;
WHILE @counter < 5
   BEGIN
      SELECT RAND() Random_Number
      SET @counter = @counter + 1
   END;
GO

Reference

Other Resources

Help and Information