Subject Grant role by script


Using FlameRobin, I can run this statement

GRANT rdb$admin TO USER MyUser;

However, I can't seem to run it in a script. I have a master script file that runs a set of files. I tried it in a file, and directly

1) %SqlExe% -user '%Usr%' -password '%Pwd%' -input ..\Tables\aaaGrant.sql -echo -output %OutFile%

2) %SqlExe% -user %Usr% -password %Pwd% GRANT rdb$admin TO USER LegacyUser;

Is there a way to do this by script?