# Planning for Week 7

## High Level Topic Summary

> - Hierarchical Data Model Completion
>     - XPath
>     - Constraints and Enforcement

## Readings for the week

Day        | Reading      | Reading Questions
:--------- |:-------------|:----------------------------------
Monday     | Chapter 16, 16.4 | None
Tuesday    | - | Quiz2
Wednesday  | Chapter 17, 17.1, 17.2 | none
Friday     | Chapter 17, 17.4 (XML Schema) | 17.4, 17.5, 17.6, 17.7

## Projected Class and Homework

HW | Day Out  | Day Due | Contents
:--|:--------|:--------|:------------
- | Monday | Wednesday | -
HW_2.8 | Wednesday | Friday | XPath
- | Friday | Monday | -

## Tuesday Problem Day

Quiz 2 on Tabular transformations, tidy data normalization, JSON and XML.

## Progression

We start the week reviewing (through Q & A) the topics to be covered in the second Quiz of the semester.  With those topics concluding with XML operations, we can start to look at XPath as a declarative alternative to the procedural traversal and access operations for working with XML trees.  On Wednesday, we build out more XPath and integrate that with programmatically constructing tabular data sets.  Friday, we address the constraints of the model, more formally defining the syntactic rules and then layering constraints that specify value and tree-relationship limitations on an XML structure.