tkinter - I want to get an error message on entering wrong value inside a entrybox but instead I get an success message on every entry

Question

I have a code where I input a wrong value or a value which is not situated in the database and I want an error message box to show up But instead, I get an error Messagebox on every entry given in the entry box Please Provide a solution to this issue even though the entry given is not located in the database

             def deldata(self):
                 self.a=self.entry4.get()
                 cursor=dd.cursor()
                 cursor.execute("DELETE FROM stbook WHERE Book_ID='"+self.a+"'")
                 dd.commit()
                 self.da=cursor.fetchone()
                 if self.da!=None:
                      messagebox.showinfo('Hotel System','Guest is Deleted successfully !')
                 else:
                      messagebox.showerror('Hotel System','Guest is not Found in Database')

Answer 1

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