Net8 Connect Strings

Hi,

I recently tried to define an Oracle 8 database for Cognos Impromptu. If you use native Oracle drivers, Impromptu requires the connect string. I am definitely a novice when it comes to Oracle, but I took an entry out of the tnsnames.ora file and tried to enter it into the text box supplied for the connect string. It didn't work...I got it working using ODBC, but I'd like to know if tnsnames.ora was the right place to look for this information. How would I construct a connect string for an Oracle database? What are the various pieces of information needed to construct one? Is there any sort of saving using native drivers over ODBC? Thanks in advance!

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Kevin MacLeod