Exam topics
- Native XML databases vs. XML-enabled relational databases; data model (XDM): tree (nodes for document, elements, attributes, texts, …), document order, reverse document order, sequences, atomic values, singleton sequences
- XPath language: path expressions (relative vs. absolute, evaluation algorithm), path step (axis, node test, predicates), axes (forward: child, descendant, following, …; reverse: parent, ancestor, preceding, …; attribute), node tests, predicates (path conditions, position testing, …), abbreviations
- XQuery language: path expressions, direct constructors (elements, attributes, nested queries, well-formedness), computed constructors (dynamic names), FLWOR expressions (for, let, where, order by, and return clauses), typical FLWOR use cases (joining, grouping, aggregation, integration, …), conditional expressions (if, then, else), switch expressions (case, default, return), universal and existential quantified expressions (some, every, satisfies), comparisons (value, general, node; errors), atomization of values (elements, attributes)