Coveo indexes external database in Sitecore 8
I have Coveo 4.0 installed with Sitecore 8.2 website. By default, it created a Sitecore Search Provider collection with 2 sources(Coveomasterindex-servername-applicationname and Coveowebindex-servername-applicationname) inside. Then, I manually added the 3rd source called "External_DB" connects to a SQLServer database to grab some sample data and indexed by Coveo. Everything works well so far.
After creating a Coveo search sample page in Sitecore, I can search everything within Sitecore website.
The question is: how do I make the data from the SQLServer searchable in Sitecore website? I only see the 2 sources available in Sitecore index manager: Coveomasterindex-xxxx and Coveowebindex-xxxx)
I think you should follow this documentation: https://developers.coveo.com/display/SitecoreV4/Enabling+the+External+Source+in+Sitecore
By default, Coveo for Sitecore only displays items from your Sitecore instance, but it is easy to change that.
Since you are working with 8.2, however, there is a bug with the Rule Editor in the Experience Editor (only available with Enterprise and Enterprise Cloud). In that case, you should modify the rule by going to Presentation > Details.
Let me know if it works! :)