Is there a way of opening a part or drawing and seeing which assembly its used on?
No, but you can use SW Explorer and run a where-used search. The one limitation is that it will only search where you tell it to, so if you don't know where the assembly file is located, you have a problem.
there is no direct way but you can Try : right click on the file, choose solidworks and then rename per exemple and the software will search for any file that uses that part
Most PDM systems, including SolidWorks Workgroup and Enterprise PDM, incorporate this kind of functionality.
The trick to getting it to work is knowing where to look for the parent references. In a PDM system, usually the entire vault is indexed, so the results are nearly instantaneous.
You can also do a where-used search using SolidWorks Explorer (which can be launche from the Tools menu if you have solidworks open). You just have to specify which folders to search in the SolidWorks Explorer Options dialog box.
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