While I've not yet had the pleasure of playing with MBLs, a few points come to mind. Security If people wish to write their own libnames then they will need all the connection information, including passwords, in order to do this. Enforcing access through metadata will mean that connection details stay within the realm of admins. Portability A non-MBL libname will not be portable. Thus a program developed in a Dev environment and promoted through other environments, eventually to Prod, would need to change that libname statement in each environment. A MBL would pick up everything it needs from the metadata in the current environment, irrespective of the environment. Similarly, if a database is moved to a different server, or a password changed - a MBL libname statement would not need to be modified. Passthrough I may have this wrong, but I believe a MBL greatly simplifies specifying connection details for SQL passthrough and means that actual connection details are not required. By the way, what is "data at rest"? Never heard this term before.
... View more