Generating random strings with T-SQL

Question

If you wanted to generate a pseudorandom alphanumeric string using T-SQL, how would you do it? How would you exclude characters like dollar signs, dashes, and slashes from

Answer 1

For SQL Server 2016 and later, here is a really simple and relatively efficient expression to generate cryptographically random strings of a given byte length:

--Generates 36 bytes (48 characters) of base64 encoded random data
select r from OpenJson((select Crypt_Gen_Random(36) r for json path)) 
  with (r varchar(max))

Note that the byte length is not the same as the encoded size; use the following from this article to convert:

Bytes = 3 * (LengthInCharacters / 4) - Padding