XQuery 1.0: An XQL Query Language

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XQuery 1.0 An XQL Query Language
http//www.mcsr.olemiss.edu/ppt/XQuery.ppt Attemp
t by W3C at a standard query language for
XML.Has been called the SQL for XML W3C
Candidate Recommendation (3 November 2005)
Current Status Waiting for implementations. ..
. Next W3C Proposed Recommendation ??
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XQuery 1.0 Miscellany
What Came Before? XQL XML Query
Language XML-QL A Query Language for XML XPath
XML Path Language (W3C 1999) Related
Technologies XSLT XML Stylesheet Language
Transformations (W3C 1999) XPointer XML Pointer
Language (W3C 2001) XMLBeans a technology for
accessing XML by binding it to Java types A
bunch of other stuff XStuff
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XQuery Early Implementations
Commercial Implementations Relational XQuery
Abacus Systems. 30 day trial. XMLSpy 2005
Altova. 30 day trial. XHive/DB X-Hive.
Commercial. Web demo.Oracle SQL Server Open
Source Implementations Galax Open Source Mono
Project Open Source XMLBeans a technology for
accessing XML by binding it to Java types
More implementations. http//www.w3.org/XML/Que
ry/
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Tree Representation of an XML Document, D Figure
1 from TIMBER A native XML Database
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The personnel of a department can be faculty,
A Relational Schema
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The personnel of a department can be faculty,
lecturers,
A Relational Schema
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The personnel of a department can be faculty,
lecturers, or scientists.
A Relational Schema
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They may or may not have a secretary.
A Relational Schema
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A lecturer can have TAs, no RAs.
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A scientist can have RAs, but no TAs.
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Each faculty may have both TAs and RAs.
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Data Type Definition (DTD) for Amber XML document
z department faculty lecturer scientist)) staff ( name, (secretary?) ) faculty (name, secretary?, ta, ra)


(PCDATA)

The personnel of a department can be staff,
faculty, lecturers, or scientists.
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XML
..
.
. .artment
The personnel of a department can be staff,
faculty, lecturers, or scientists.
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DTD
z department faculty lecturer scientist)) staff ( name, (secretary?) ) faculty (name, secretary?, ta, ra)


(PCDATA)

Each of them has a name as identification.
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DTD
z department faculty lecturer scientist)) staff ( name, (secretary?) ) faculty (name, secretary?, ta, ra)


(PCDATA)

They may or may not have a secretary.
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XML
T.Brown
Each of them has a name as identification.
K.Blue
M.Black
They may or may not have a secretary.
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DTD
z department faculty lecturer scientist)) staff ( name, (secretary?) ) faculty (name, secretary?, ta, ra)


(PCDATA)

Each faculty may have both TAs and RAs.
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XML
K.Blue
M.Black
Peter Bob
Pam DJ
Each faculty may have both TAs and RAs.
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DTD
z department faculty lecturer scientist)) staff ( name, (secretary?) ) faculty (name, secretary?, ta, ra)


(PCDATA)

A lecturer can have one or more TAs, but no RA..
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DTD
z department faculty lecturer scientist)) staff ( name, (secretary?) ) faculty (name, secretary?, ta, ra)


(PCDATA)

A scientist can have any number of RAs, but no
TA.
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http//willow.olemiss.edu/engr654/timber2.php
Bring up the Timber XML document in a web
browser. http//www.mcsr.olemiss.edu/d.xml
In a separate browser, connect to the Timber 2
relational DB.
http//willow.olemiss.edu/engr654/timber2.php
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SQL SELECT Syntax
SELECT DISTINCT ALL column_expression1,
column_expression2, .... FROM from_clause
WHERE where_expression GROUP BY expression1,
expression2, .... HAVING having_expression
ORDER BY order_column_expr1,
order_column_expr2, .... column_expression
expression AS column_alias
from_clause select_table1, select_table2,
... from_clause select_table1 LEFT OUTER
JOIN select_table2 ON expr ... from_clause
select_table1 RIGHT OUTER JOIN select_table2 ON
expr ... from_clause select_table1 INNER
JOIN select_table2 ... select_table
table_name AS table_alias select_table
( sub_select_statement ) AS table_alias
order_column_expr expression ASC DESC

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Querying Timber 2 relational DB with
SQL http//willow.olemiss.edu/engr654/timber2.php
See Relational DB Design 2 on handout (page ??)
Write an SQL Query toList the names of all
faculty members.
select staff.name from faculty, staffwhere
faculty.id staff.id
Enter the query in the text box of the web
pageand click Submit Query
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The XQuery FLWOR expression
For-Let-Where-Order-Return pronounced "flower"
generalizes SELECT-FROM-HAVING-WHERE from SQL
http//www.brics.dk/amoeller/XML/querying/flwrexp
.html
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XQuery FLWOR
See d.xml on handout pg ? or at
http//www.mcsr.olemiss.edu/d.xml
1. List the names of all faculty members.
K.Blue
M.Black
for fac in doc("http//www.mcsr.olemiss.edu/d.xm
l")//faculty
return fac/name
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XQuery FLWOR Lets Try one.
See d.xml on handout pg ? or at
http//www.mcsr.olemiss.edu/d.xml
1. Web browse to http//support.x-hive.com/xquer
y/
List the names of all faculty members.
2. Select XQuery Updates 1 from dropdown menu
K.Blue
M.Black
3. Enter this XQuery expression in theleft text
box, then Submit Query.
for faculty in doc("http//www.mcsr.olemiss.edu/
d.xml")//faculty
return faculty/name
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XQuery FLWOR
See d.xml on handout pg ? or at
http//www.mcsr.olemiss.edu/d.xml
for fac in doc("http//www.mcsr.olemiss.edu/d.xm
l")//faculty
return fac/name
K.Blue
M.Black
Peter Bob
Pam DJ
2. List the names of all TAs working for
faculty, (not for lecturers)
Who can build this XQuery first?
for fac in doc("http//www.mcsr.olemiss.edu/d.xm
l")//facultyreturn fac/ta
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XQuery FLWOR
See d.xml on handout pg ? or at
http//www.mcsr.olemiss.edu/d.xml
for fac in doc("http//www.mcsr.olemiss.edu/d.xm
l")//faculty
return fac/name
K.Blue
M.Black
Peter Bob
Pam DJ
3. List the names of all faculty members
(without XML tags)
for fac in doc("http//www.mcsr.olemiss.edu/d.xm
l")//facultyreturn data(fac/name)
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XQuery FLWOR
See d.xml on handout pg ? or at
http//www.mcsr.olemiss.edu/d.xml
4. List the names of all faculty members
(without tags)in an unordered list
K.Blue
M.Black
Peter Bob
Pam DJ

for fac in doc("http//www.mcsr.olemiss.
edu/d.xml")//facultyreturn
• data(fac/name)/li

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for fac in doc("http//www.mcsr.olemiss.
edu/d.xml")//facultyreturn
• data(fac/name)/li

5. List the names of all RAs working for
scientists (without XML tags)sorted
alphabetically,in an ordered html list.
L.Young
P.White
Todd Ann
Lisa
Who can solve first?

for ra in doc("http//www.mcsr.olemiss.e
du/d.xml")//scientist/raorder by data (
ra) return
1. data(ra)

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for ra in doc("http//www.mcsr.olemiss.e
du/d.xml")//scientist/raorder by data (
ra) return
1. data(ra)

L.Young
P.White
Todd Ann
Lisa
6. List the secretary names (without XML tags or
HTML tags) of all employees,sorted alphabetically
Who can solve first?
for sec in doc("http//www.mcsr.olemiss.edu/d.xm
l")///secretaryorder by data( sec) return
data(sec)
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References
http//www.w3.org/TR/xquery/ http//xmlbeans.apach
e.org/ http//www.stylusstudio.com/xquery_primer.h
tml http//www.w3schools.com/xquery/xquery_flwor_h
tml.asp http//www.brics.dk/amoeller/XML/querying
/flwrexp.html http//www.xmlfiles.com/dtd/dtd_elem
ents.asp http//support.x-hive.com/xquery/ http//
www.saxonica.com/documentation/javadoc/index.html
http//www.stylusstudio.com/xquery_primer.html htt
p//www.oracle.com/technology/tech/xml/xquery/inde
x.html