server: fix update stock

server.rb

@@ -311,6 +311,8 @@ def add_part(part)
   field = "location"
   part[field] = nil if part[field] and 0 == part[field].length
   if part[field] then
+    delete = @db.prepare("DELETE FROM inventory WHERE part = ?")
+    delete.execute(part["id"])
     statement = @db.prepare("SELECT id FROM #{field} WHERE LOWER(name) = ?")
     ref = statement.execute(part[field].downcase).to_a[0]
     unless ref then