From 890ad2bcee172ab2a4cbb319145f5b42ba38619a Mon Sep 17 00:00:00 2001
From: Julian T <julian@jtle.dk>
Date: Thu, 25 Nov 2021 08:47:19 +0100
Subject: Add notes and assignment solution

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+
+Xpath is used for quering information in XML documents.
+Can also be used with postgresql databases.
+
+When using xpath, we query an abstact document structure.
+This is also represented by a nodetree.
+
+NOTE that `/, /something/else` in the slides are two different queries.
+
+# Nodetree
+
+**Document node** is the root of the tree, thus the whole element.
+Will often contain document metadata, and will point at a single root element.
+
+**Element** element represent nodes.
+
+# Location Step
+
+Stuff between two `/`'s.
+Looks like `${axis}::${node test}[${predicate_1}][${predicate_2}]`
+
+Axis will default to `child`.
+But there are many other, which also have abbreviations.
+
+# Funktioner og Expressions
+
+Man kan køre funktioner såsom concat.
+Og de kan bruge queries.
+
+```
+concat("hej", /med/dig/text())
+```
+
+# Spørgsmål
+
+Vil det her give root element flere gange.
+```
+//course/..
+```
+
+Nope det er sets, den vil ikke være der flere gange.
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