Where should I handle exceptions in BLL, DAL or PL?

Question

What is the best place to handle exceptions? BLL, DAL or PL?

Should I allow methods in DAL and BLL to exclude exceptions from the chain and let the PL handle them? Or should I process them in BLL?

eg

If I have a method in my DAL that returns “ExecuteNonQuery” and updates some records, and for one or more reasons, 0 rows will suffer. Now, how should I inform my PL about whether an exception occurred or if there really weren’t any rows matching the condition. Should I use "try catch" in my PL code and report it through the exception, or do I need to handle the exception in DAL and return some special code, for example (-1), to allow PL to distinguish between (exception) and (no line matches condition, i.e. zero lines are affected)?

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Of course, you will not receive detailed messages about exceptions, but this is good for your users. You must have a flexible logging system to catch these exceptions and report this to the database or ip port: or whatever you decide.

Essentially, you need to think about separation of problems if the problem is related to a data problem or a logical problem with which it should be handled accordingly.