4 files changed, 72 insertions, 0 deletions
diff --git a/Year_2/Databases/README.md b/Year_2/Databases/README.md
new file mode 100644
index 0000000..5af8687
--- /dev/null
+++ b/Year_2/Databases/README.md
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+# XQuery
+XQuery files are compiled by xqilla.
+
+[debian](https://packages.debian.org/bullseye/xqilla) | [ubuntu](https://packages.ubuntu.com/focal/xqilla)
diff --git a/Year_2/Databases/university_marks.dtd b/Year_2/Databases/university_marks.dtd
new file mode 100644
index 0000000..caab080
--- /dev/null
+++ b/Year_2/Databases/university_marks.dtd
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+<!ELEMENT libretti (libretto)*>
+<!ELEMENT libretto (studente, esami)?>
+<!ELEMENT studente (nome, cognome)>
+<!ELEMENT nome (#PCDATA)>
+<!ELEMENT cognome (#PCDATA)>
+<!ATTLIST studente
+    cdl CDATA #REQUIRED
+    matricola CDATA #REQUIRED
+>
+<!ELEMENT esami (esame)+>
+<!ELEMENT esame (materia, data, voto)>
+<!ELEMENT materia (#PCDATA)>
+<!ELEMENT data (#PCDATA)>
+<!ELEMENT voto (#PCDATA)>
diff --git a/Year_2/Databases/university_marks.xml b/Year_2/Databases/university_marks.xml
new file mode 100644
index 0000000..fcd0eb5
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+++ b/Year_2/Databases/university_marks.xml
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+<?xml version="1.0" ?>
+<!DOCTYPE libretti SYSTEM "university_marks.dtd">
+<libretti>
+    <libretto>
+        <studente cdl="Computer engineering" matricola="0000122">
+            <nome>Luke</nome>
+            <cognome>Don</cognome>
+        </studente>
+        <esami>
+            <esame>
+                <materia>Algebra</materia>
+                <data>2021-02-02</data>
+                <voto>30</voto>
+            </esame>
+        </esami>
+    </libretto>
+    <libretto>
+        <studente cdl="Computer science" matricola="0000123">
+            <nome>John</nome>
+            <cognome>Doe</cognome>
+        </studente>
+        <esami>
+            <esame>
+                <materia>Databases</materia>
+                <data>2021-02-06</data>
+                <voto>18</voto>
+            </esame>
+        </esami>
+    </libretto>
+    <libretto>
+        <studente cdl="Computer science" matricola="0000125">
+            <nome>Mark</nome>
+            <cognome>Zuck</cognome>
+        </studente>
+        <esami>
+            <esame>
+                <materia>Databases</materia>
+                <data>2021-02-06</data>
+                <voto>30</voto>
+            </esame>
+        </esami>
+    </libretto>
+</libretti>
diff --git a/Year_2/Databases/university_marks.xquery b/Year_2/Databases/university_marks.xquery
new file mode 100644
index 0000000..e2f0e4e
--- /dev/null
+++ b/Year_2/Databases/university_marks.xquery
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+<students>
+{
+for $student in doc("university_marks.xml")//libretto
+where $student/esami//voto/text()=30
+return <student>
+    {$student/studente/nome/text()}
+    { ' ' }
+    {$student/studente/cognome/text()}
+    </student>
+}
+</students>