Parsing XML Streams with SAX

When XML documents are too large to load into memory as a DOM tree, event-based parsers like SAX offer a streaming alternative. SAX fires callbacks at tag start and end events, but disambiguating elements with the same name (e.g., nested <name> tags) requires extra context tracking. A clean general solution is to maintain a stack of visited tags: push on startElement, pop on endElement. This gives you parent lookup, ancestor checks, and full path reconstruction with minimal overhead. A Python example using xml.sax demonstrates the pattern with a sample company/employee XML structure.