Re: running instantclient sqlplus without tnsnames.ora file?

It's possible. It's even documented.

From the OTN download screen for Instant Client on OTN, I read

"

Get on the Grid. Now.

Download and be ready in seconds. Deploy your applications right out of the box. Deliver the promise. Free.

Description

Instant Client allows you to run your applications without installing the standard Oracle client or having an ORACLE_HOME. OCI, OCCI, Pro*C, ODBC, and JDBC applications work without modification, while using significantly less disk space than before. Even SQL*Plus can be used with Instant Client. No recompile, no hassle.
"

Amusingly the 4 installation steps are on the bottom of the download screen.

ps: the download page also has a download for "Additional libraries and executable for running SQL*Plus with Instant Client"

-- 
Hans Forbrich                           
Canada-wide Oracle training and consulting
mailto: Fuzzy.GreyBeard_at_gmail.com   
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