Sql Syntax Question - Dynamically create an externally identified account

Hello,

I am trying to write a script that will create an externally identified oracle account, but I need to pass a variable to the script to be incorporated into the account name as my unix accounts are named specific to my database name.  For example, my database name for the first db might be testadb and the second testbdb.  The unix account for the first db would be oratesta and the unix account for the second, oratestb.  In this scenario, the ops accounts needed would be ops$oratesta and ops$oratestb.  I am trying to script my create statement to accept a