Hi Wahaj,
If the SQL Server Reporting Services(SSRS) is a 64-bit version, please install the 64-bit Oracle client.
However, since Business Intelligence Development Studio(BIDS) is a 32-bit application, in order to connect the Oracle from BIDS, we need to install the 32-bit Oracle client. I would suggest you install 32-bit Oracle client on a Dev server, which contains
BIDS. And install the 64-bit Oracle client on the SSRS product server, which is a different server.
Please design the report in the 32-bit environment, and then deploy the report to 64-bit SSRS server.
If there is anything unclear, please feel free to ask.
Thanks,
Jin Chen
Jin Chen - MSFT