DSXchange

I need a clarification about ODBC stages and ORACLE OCI stages.
In ODBC stage we use the DSN name that we have created via
ODBC connectivity.But in ORACLE OCI only if we give the
service name it works fine.But still in the general tab of the OCI stage
DAtabase source name only is given not the service name!
Then why do we use service name?

--SumA

Both stages work in a similar fashion, but are configured using different mechanisms. Both use a DSN - a Data Source Name - which is simply a marker or label for a set of configuration information. The DSN can bear absolutely no resemblance to what it actually connects to, but are generally made the same to avoid confusion.

As you've stated, ODBC has its own configuration file where you setup the DSN. Oracle has something similar called "tnsnames.ora" which is typically found in $ORACLE_HOME/network/admin. What you specify as the DSN for Oracle is the name of the entry in the tnsnames file you want to use to connect. Inside the entry is the actual Service Name or SID for the instance you are trying to connect to.

Can i take it in this way.
Even though i am creating a DSN name for ODBC Stage ,Internally it is only the service name or SID in tnsnames.ora that Functions.
SO internally both the servicename and the DSN name functions in the same way. Can i frame a Rule that service id only should be used for ORACLE OCI stages and DSN name should be used for OCI stages.

Correct me if i am wrong!!

I'm a little lost in what you are saying, but keep in mind the fact that the ODBC and OCI stages are configured separately and that one has no idea what you've setup for the other.