When you are analyzing an application having both application source code and DB objects and after analysis you notice missing links between the application and DB objects then the first think to check here is whether the application source code analysis has loaded the external links or not.
Open the analysis log of application source code and check for external links object loaded, search for this line:
External link component has loaded 0 objects
If the number of object loaded is 0 then it is obvious that so external objects has been loaded for external links.
So further check if there is a proper dependency set between the technos (application + DB).
If no then set the required dependency and run the analysis again.
If yes then check from the analysis log date and time which analysis has run first. Ideally is dependency is set DB source code analysis should run first. If this is not the case here (when application analysis has run first) then it is obvious that no external objects are available for application source code to make the link.
So as a solution to get link you need to run the application analysis again and check for the External Link component loaded how many objects. If there are numbers then it means there would be required links created between the technos.