Pass the URL of the Oracle server with URL env var:
$ docker run -e URL=<user>/<password>@//<address>:<PORT>/<DATABASE> -ti sflyr/sqlplus
SQL*Plus: Release 11.2.0.3.0 Production on Tue Aug 11 15:41:07 2015
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Release 11.2.0.1.0 - 64bit Production
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