What do you do when, connecting to Oracle 9 using standard DB client from .Net, an error message informs you that at least Oracle version 8.1.7 or higher is needed? We did encounter such a problem while working on a project. Thankfully, after some searching and asking, a solution could be found — read on if you are looking for an answer too.
We saw this issue while creating a standalone ATP/CTP* Client (you can read more about this product on the site of our partner, techwire UK, in the feature titled “Web-based Ordering”) for I-Plan, a supply-chain management application. This client (and the corresponding server-side enhancement) is an application that allows to demonstrates the ATP/CTP logic, usually “hidden” within the main I-Plan core, and also it provides possibility for external systems to send ATP/CTP requests to I-Plan using a web-service API.
System.Data.OracleClient requires Oracle client software version 8.1.7 or greater
So, it would seem that at least Oracle version of 8.1.7 was needed, or greater — while we were using 9! Additional difficulty in investigating and solving the problem was that it didn’t occur on all the servers that we tried it on. So it took us some time to find a solution, therefore we hope it may be useful to you someday.
To solve it, we had to perform the steps below on every server where the issue occurs — so there is no generic programmatic solution to this, unfortunately. It is required to give the authenticated user a privilege to the Oracle Home in Oracle 9.2 Client software, as follows:
Permission = Read & Execute
Apply To = This folder, subfolders and files
If this is NOT the case, edit that line and make sure the “Apply onto” drop-down box is set to “This folder, subfolders and files”. This should already be set properly but it is important that you verify this.
And then it works!
As you can see the solution is far from obvious, especially if one looks at the original error message. Thankfully, there is a helpful development community around Oracle and .Net, so we found the above on one of the forums. Please feel free to post your feedback or questions in the comment form below.
* — ATP/CTP stands for “Available To Promise” and “Capacity To Promise”, two modes for ordering items, the former checking whether the item is available in inventory (across several warehouses, in our case), the latter checking if there is available production capacity to manufacture the required quantity of the material in time.