Stored procedure to generate a simple or complex random password

This procedure generates random passwords using RAND() function. It can be configured to generate a simple or a complex password. You can also customize the length of the password generated. Complex passwords will include upper and lower case letters, numbers and special characters. See the code to realize how useful the RAND() function is! When you choose to generate a simple password (default behavior), SPECIAL CARE is taken to generate meaningful/easy to remember passwords.

CREATE PROC random_password
(
@len int = 8, --Length of the password to be generated
@password_type char(7) = 'simple'
--Default is to generate a simple password with lowecase letters.
--Pass anything other than 'simple' to generate a complex password.
--The complex password includes numbers, special characters, upper case and lower case letters
)
AS

/*Purpose: To generate a random password

Examples:

To generate a simple password with a length of 8 characters:
EXEC random_password

To generate a simple password with 6 characters:
EXEC random_password 6

To generate a complex password with 8 characters:
EXEC random_password @Password_type = 'complex'

To generate a comples password with 6 characters:
EXEC random_password 6, 'complex'

*/
BEGIN
DECLARE @password varchar(25), @type tinyint, @bitmap char(6)
SET @password=''
SET @bitmap = 'uaeioy'
--@bitmap contains all the vowels, which are a, e, i, o, u and y. These vowels are used to generate slightly readable/rememberable simple passwords

WHILE @len > 0
BEGIN
IF @password_type = 'simple' --Generating a simple password
BEGIN
IF (@len%2) = 0 --Appending a random vowel to @password

  SET @password = @password + SUBSTRING(@bitmap,CONVERT(int,ROUND(1 + (RAND() * (5)),0)),1)
ELSE --Appending a random alphabet
  SET @password = @password + CHAR(ROUND(97 + (RAND() * (25)),0))

END
ELSE --Generating a complex password
BEGIN
  SET @type = ROUND(1 + (RAND() * (3)),0)

  IF @type = 1 --Appending a random lower case alphabet to @password
   SET @password = @password + CHAR(ROUND(97 + (RAND() * (25)),0))
  ELSE IF @type = 2 --Appending a random upper case alphabet to @password
   SET @password = @password + CHAR(ROUND(65 + (RAND() * (25)),0))
  ELSE IF @type = 3 --Appending a random number between 0 and 9 to @password
   SET @password = @password + CHAR(ROUND(48 + (RAND() * (9)),0))
  ELSE IF @type = 4 --Appending a random special character to @password
   SET @password = @password + CHAR(ROUND(33 + (RAND() * (13)),0))
END