Native XML databases - Making Sense of NoSQL - page 118

The TEI documents contain many entities (people, dates, terms) that are annotated
with TEI tags. For example, each person has a <person> tag wrapping the name of the
individual mentioned. A sample of these tags is shown in table 5.2.

Table 5.2 Sample of TEI entity annotations for people, dates, glossary terms, and geolocations. Note
that an XML attribute such as corresp for persons is used to reference a global dictionary of entities.
Annotations are wrappers around text to describe the text. Attributes such as corresp="" are key-
value pairs within the annotation elements that add specificity to the annotations.

Entity type Example

Person

<persName corresp="nixon-richard-m">the president</persName>

Date <date when="1967-06-09">June 9th</date>

Glossary term

<gloss target="t_F41">Phantom F-4 aircraft</gloss>

Geolocations

<placeName key="t_ROC1">China</placeName>

XQuery makes it easy to query any XML document for all entities within the docu-
ment. For example, in figure 5.11 the XPath expression //person will return all per-
son elements found in a document including those found at the beginning, in the
middle, and at the end.
An important note to this project: it was done on a modest budget, by nontechni-
cal internal staff and limited outside contractors. The internal staff had no prior

Figure 5.11 Each page of the FRUS document lists the entities found on that page. For
example, the people and terms referenced in this page are also shown in the right margin
of the page. Users can click on each entity for a full definition of that person or term.