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XML Databases
13. Systems
Silke Eckstein
Andreas Kupfer
Institut für Informationssysteme
Technische Universität Braunschweig
http://www.ifis.cs.tu-bs.de
13. Systems
13.1 Introduction
13.2 Oracle
13.3 DB2
13.4 SQL Server
13.5 Tamino
13.6 Summary
13.X Overview and References
XML Databases – Silke Eckstein – Institut für Informationssysteme – TU Braunschweig
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13.1 Introduction
• After discussing various aspects of XML and XML databases ...
• ... we are now going to have a closer look at some of the database
systems.
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13.1 Introduction
• RDBMS with XML support
• Native XML-DBMS systems
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13. Systems
13.1 Introduction
13.2 Oracle
13.3 DB2
13.4 SQL Server
13.5 Tamino
13.6 Summary
13.X Overview and References
XML Databases – Silke Eckstein – Institut für Informationssysteme – TU Braunschweig
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13.2 Oracle 11g
Architecture
Figure taken from Oracle®
XML Developer's Kit
Programmer's Guide 11g
Release 1 (11.1), April 2008
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13.2 Oracle 11g
Architecture (2)
Figure taken from Oracle®
XML DB Developer’s
Guide 11g Release 1 (11.1)
October 2007
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13.2 Oracle 11g
• Mapping variants from XML to databases
– XML column approach: Column is based on XML type
– XML table approach: Table is based on XML type
• Using objectrelational extensions of Oracle
– XMLTYPE as predefined object type with SQL/XML
functions as methods
– Intermedia-Text-Package with full text functions
– DBMS_XMLDOM package with DOM methods
– DBMS_XMLSCHEMA package with administration and
generation methods
– DBMS_XMLGEN package with methods to generate XML
from SQL
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13.2 Oracle 11g
• Storage options
–
–
–
–
text-based (unstructured as CLOB)
binary (compact storage in XML binary format)
schema-based (object-relational storage requires XML Schema)
hybrid (semistructured)
Figure taken from
Oracle® XML DB
Developer’s Guide
11g Release 1 (11.1)
October 2007
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13.2 Oracle 11g
Figure taken from
Oracle® XML DB
Developer’s Guide
11g Release 1 (11.1)
October 2007
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13.2 Oracle 11g
• XML-column vs. XML-table approach
– Table with XML column
CREATE TABLE <table name> ( <column name> XMLTYPE)
[XMLTYPE [COLUMN] <column name>
[STORE AS {OBJECT RELATIONAL | CLOB ( <LOB parameter>) | BINARY XML ( <LOB parameter>) })
[XMLSCHEMA <url> ELEMENT [ <url> #] <element> ]]
schema-based
text-based
binary
– XML table
CREATE TABLE <table name> OF XMLTYPE
[XMLTYPE
[STORE AS {OBJECT RELATIONAL | CLOB ( <LOB parameter>) | BINARY XML ( <LOB parameter>) })
[XMLSCHEMA <url> ELEMENT [ <url> #] <element> ]]
– Inserting documents in both cases
INSERT INTO table VALUES (XMLTYPE (getDocument('input1.xml')));
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13.2 Oracle 11g
• User-defined function getDocument(file) to
read XML documents
CREATE DIRECTORY xmldir AS 'c:\xmldir';
GRANT READ ON DIRECTORY xmldir TO PUBLIC WITH GRANT OPTION;
CREATE FUNCTION getDocument(filename VARCHAR2)
RETURN CLOB
AUTHID CURRENT_USER IS
xbfile BFILE;
xclob CLOB;
BEGIN
xbfile := BFILENAME('xmldir', filename);
DBMS_LOB.open(xbfile);
DBMS_LOB.createTemporary(xclob TRUE, DBMS_LOB.session);
DBMS_LOB.loadFromFile(xclob, xbfile,
DBMS_LOB.getLength(xbfile));
DBMS_LOB.close(xbfile);
RETURN xclob;
END;
/
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13.2 Oracle 11g
• Package DBMS_XMLSCHEMA offers methods
to register, compile, generate and delete XML
Schemas
DBMS_XMLSCHEMA.registerSchema( 'schema-URL', 'schema-name' );
DBMS_XMLSCHEMA.registerSchema( 'text.xsd', getDocument('test.xsd') );
DBMS_XMLSCHEMA.compileSchema( 'schema-URL' );
DBMS_XMLSCHEMA.generateSchema( 'schema-URL', 'type-name' );
DBMS_XMLSCHEMA.deleteSchema( 'schema-URL', DeleteOption );
DeleteOption:
DELETE_RESTRICT
DELETE_INVALIDATE
DELETE_CASCADE
DELETE_CASCADE_FORCE
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13.2 Oracle 11g
• Some methods of the XMLTYPE
– XMLTYPE(<value-expr>) is the constructor. Expression can be a string or a
user defined type
– getClobVal()/getStringVal() returns XML value as CLOB or string
– getNumVal() only applicable to text nodes containing a numeric string
– isFragment() returns 1 if instance has more than one root element
– existsNode(<XPath-expr>) returns 1 if the expression returns a node
– extract(<XPath-expr>) extracts a part of the XML value
– transform(<XML-value-expr>) transforms according to a stylesheet
– toObject() converts to an object
– isSchemaBased() returns 1 if the XML value is based on a schema
– getSchemaURL() returns the URL to the schema
– getRootElement() returns the root element or NULL for fragments
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13.2 Oracle 11g
• Queries
– Support of SQL/XML functions
•
•
•
•
•
•
•
XMLQUERY
XMLTABLE
XMLAGG
XMLELEMENT
XMLATTRIBUTE
XMLFOREST
…
– And additional functions
• EXTRACT
• EXISTSNODE
• ...
– Full text search with the Intermedia-Text-Package
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13.2 Oracle 11g
• EXTRACT
– extracts an excerpt of the XML value described by an
XPath query
EXTRACT( <XML-value-expression>, <XPath-expression> [, <Namespace>] )
SELECT
EXTRACT( VALUE(b), '//@ISBN' ) AS ISBNumber,
EXTRACT( VALUE(b), '//Title/text()' ) AS Title_content,
EXTRACT( VALUE(b), '//Title' ) AS Title_element
FROM Book b;
ISBNumber
Title_content
Title_element
3-89864-148-1
XML &amp; Datenbanken
<Title>XML &amp; Datenbanken</Title>
3-89864-219-4
SQL-1999 &amp; SQL:2003
<Title>SQL-1999 &amp; SQL:2003</Title>
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13.2 Oracle 11g
• EXISTSNODE
– Returns 0 if the query returns the empty sequence
EXISTSNODE( <XML-value-expression>, <XPath-expression> [, <Namespace>] )
Example:
SELECT
EXTRACT( VALUE(b), '//@ISBN' ) AS ISBNumber,
EXTRACT( VALUE(b), '//Title/text()' ) AS Title_content,
EXTRACT( VALUE(b), '//Title' ) AS Title_element
FROM Book b
WHERE EXISTSNODE( VALUE(b), '//Book[@ISBN="3-89864-219-4"]' ) = 1;
ISBNumber
Title_content
Title_element
3-89864-219-4
SQL-1999 &amp; SQL:2003
<Title>SQL-1999 &amp; SQL:2003</Title>
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13.2 Oracle 11g
• Indexing
– Full text index
CREATE INDEX xmlfulltextidx ON Book b
(VALUE(b)) INDEXTYPE IS CTXSYS.CONTEXT;
– Path index
CREATE INDEX xmlpathidx ON Book b
(VALUE(b)) INDEXTYPE IS CTXSYS.CTXXPATH;
– Functional index
(value index)
– XML index
CREATE INDEX xmlfunctionalidx ON Book b
(EXTRACTVALUE(VALUE(b),'//@year'));
CREATE INDEX xmlidx ON Book b
(VALUE(b)) INDEXTYPE IS XDB.XMLIndex;
• Creates a set of secondary indexes
– Path index with all XML tags and fragments
– Value index with the oder of the document (node positions)
– Value index to index the values of the nodes
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13.2 Oracle 11g
• Using indexes
– Query using the path index:
SELECT EXTRACTVALUE (VALUE(b),'//Title') AS Title FROM Book b
WHERE EXISTSNODE (VALUE(b),'/Book/Publisher[text()="dpunkt"]') = 1;
– Query using the full text index:
SELECT SCORE (o), EXTRACT(VALUE(b),'//@ISBN') AS ISBN FROM Book b
WHERE CONTAINS (VALUE(b),'Java', o) > o ORDER BY SCORE (o) DESC;
– Query using the functional index:
SELECT EXTRACTVALUE (VALUE(b),'//Title') AS Title FROM Book b
WHERE EXTRACTVALUE (VALUE(b),'//Year') = 2009;
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13.2 Oracle 11g
• Manipulation – UPDATEXML
– Change a part (defined by an XPath query) of the XML value
UPDATEXML (<XML-value-expr>, <replacement-list> [, <namespace>])
<replacement-list> := <XPath-expr>, <value-expr>
– Example to change the value of an attribute:
UPDATE Book b
SET VALUE(b) = UPDATEXML (VALUE(b),'//Publisher[text()="dpunkt"]/@City', 'Zürich');
• Manipulation – DELETEXML
– Deletes a sequence of nodes (selected by an XPath query)
from the XML value
DELETEXML (<XML-value-expr>, <replacement-list> [, <namespace>])
– Example to delete a specific Author node:
UPDATE Book b
SET VALUE(b) = DELETEXML (VALUE(b),'//Book[@ISBN="3-89864-148-1"]/Author[text()="Holger Meyer"]');
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13.2 Oracle 11g
• XML views
– Allow XML-based views on SQL and XML values
– Are based on the principle of object views
• The object type is XMLTYPE in this case
– Example:
CREATE VIEW DpunktBooks OF XMLTYPE
WITH OBJECT ID DEFAULT
AS SELECT VALUE (b) FROM Book b
WHERE EXISTSNODE (VALUE(b),'//Publisher[text()="dpunkt"]') ;
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13.2 Oracle 11g
•
Export of database contents with XML syntax
– Standard mapping: SQL XML with
DBMS_XMLGEN.getXML('query')
• Top level elements result from columns
• Simple types (with scalar values) as elements with PCDATA
• Structured types and their attributes as elements with subelements for
attributes
• Complex attributes as hierarchically nested elements
• Collection types are mapped to lists of elements
• Object references and referential integrity as ID/IDREF within the
document
• Table content is mapped to ROWSET elements:
<ROWSET>
<ROW num="1" > … </ROW>…<ROW num="n" > … </ROW>
</ROWSET>
– User defined transformation from SQL to XML is possible with XSLT
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13.2 Oracle 11g
• Summary Oracle XML support
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XML storage modelccccc
Extensible, object relational
Schema definition
Validation possible
Storage type
Text-based or schema-based
Mapping DB XML
By SQL/XML functions, schema
generators, XML views
XML data type
Available
Value/function index
Available
Full text index
Available
Path index
Available
Queries
SQL/XML with XQuery support
Full text search
With the Intermedia-Text-Package
Manipulation
SQL methods with XPath
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13. Systems
13.1 Introduction
13.2 Oracle
13.3 DB2
13.4 SQL Server
13.5 Tamino
13.6 Summary
13.X Overview and References
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13.3 DB2 V9
• IBM DB2
XML documents
Application
file
system
Database
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13.3 DB2 V9
• Mapping XML data to relational databases
– Variants:
• XML column approach: based on XML data type
• XML collection approach: based on decomposition of XML documents into
database tables and attributes
– Table with XML column:
• Diverse XML datatypes:
PureXML
– XML:
modelbased / hierarchical storage
– XMLCLOB:
XML documents stored as CLOBs
– XMLVARCHAR:
XML documents stored as VARCHAR XML
– XMLFILE:
XML documents stored in file system Extender
• XML schema validation for datatype XML only
• In addition: materialized views
– Extract selected XML content from documents
– Materialise those content into so-called side tables
– Side tables are defined in Document Access Definition (DAD)
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13.3 DB2 V9
• "pureXML and relational hybrid database"
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13.3 DB2 V9
• Ways to put XML
data into the
database
(PureXML)
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13.3 DB2 V9
• Ways to get
XML data out of
the database
(PureXML)
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13.3 DB2 V9
• PureXML – Queries and Indexes
– Application of SQL in XQuery:
XQUERY db2-fn:xmlcolumn (‘t1.xml1’)
– Delivers the value of column xml1 of table t1 as a node
sequence (column must be of type XML)
XQUERY db2-fn:sqlquery (’SELECT xml1 FROM t1’)
– Delivers the XML value of the single-column table t1 as a
node sequence (column must be of type XML)
– Definition of a path index:
CREATE INDEX Idx_Author_Path ON Book (Content)
GENERATE KEY
USING XMLPATTERN '//Author' AS SQL VARCHAR(50)
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13.3 DB2 V9
• XML Extender – Mapping between XML and SQL
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13.3 DB2 V9
• XML Extender – Tables with XML Types
– XML extension setup with XML Extender Admin Wizard
or Command Window:
> dxxadm enable_db XMLDB
– Definition of tables accepting XML documents:
• Variant 1: Create with XML Extender Admin Wizard
• Variant 2: SQL
CREATE TABLE Buch
(Inhalt DB2XML.XMLVARCHAR)
– Insertion of an XML document:
INSERT INTO Buch (Inhalt)
VALUES (DB2XML.XMLVARCHARFromFile('C:\XMLDIR\buch01.xml'))
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13.3 DB2 V9
• XML Extender – Queries
– SQL-XML Extender offers functions for queries and
updates
• Extract functions:
DB2XML.EXTRACT<datatype>(<XML value expression>, <XPath expression>)
• Example:
SELECT a.RETURNEDVARCHAR
FROM Buchlob, TABLE(DB2XML.EXTRACTVARCHARS(Inhalt, '//Autor')) a
– Limited supportof SQL/XML standard
• XMLAGG
• XMLELEMENT
• XMLATTRIBUTE
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13.3 DB2 V9
• ExtractXXX(<XML value expression>, <XPath expression>)
"IBM DB2 Universal Database XML Extender
Administration and Programming, Version 8, 2002"
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13.3 DB2 V9
• XML Extender – Updates
– Updates possible with special XML Extender methods
– Syntax:
DB2XML.UPDATE(<XML value expression>, <XPath expression >, <new value>)
– Restriction: predicates with elements are not supported
• Example: not supported predicate
UPDATE Buchlob
SET Inhalt = DB2XML UPDATE(Inhalt '//Verlag[text()="dpunkt"]/@Ort'
'Zürich')
• Example: supported predicate
UPDATE Buchlob
SET Inhalt = DB2XML.UPDATE(Inhalt, '// Buch[@ISBN="3-89864-1481"]/Verlag/ @Ort', 'Köln')
– With XML column approach updates are transferred to side tables
automatically
– In PureXML an XML value can only be fully replaced
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13.3 DB2 V9
• XML Extender – Indexing
– Index support
• Value index (B-Tree, Bitmap, etc.) on side tables (XML
Extender)
• Full text index (with Text Extender) on XML types
– Extension of full text index for IR on XML
• Path information included in index
• Support for path expressions
• Example:
Retrival model
SELECT Inhalt
FROM Buchlob
WHERE contains(dscrHandel, ‘MODEL order
SECTION(//Buch/Beschreibung) "Datenbank"‘) = 1
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13.3 DB2 V9
• Summary IBM DB2 XML Support
[Tür08]
XML storage model
Extensible, object relational
Schema definition
Validation possible
Storage type
Model-based (PureXML), text-based or
userdefined schema-based (XML Extender)
Mapping DB XML
DAD (XML Extender)
XML data type
Available (PureXML)
Value/function index
Standard DBS indexes on side tables
Full text index
With TextExtender
Path index
Available
Queries
SQL/XML with XQuery support
Full text search
With TextExtender
Manipulation
SQL functions with XPath
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13. Systems
13.1 Introduction
13.2 Oracle
13.3 DB2
13.4 SQL Server
13.5 Tamino
13.6 Summary
13.X Overview and References
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13.4 SQL Server
• Microsoft SQL Server Architecture
Application
XML documents
Database
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13.4 SQL Server
• Mapping XML data to relational databases
– 4 storage variants:
•
•
•
•
Native (binary) storage
Text-based storage as CLOB
Model-based storage according to EDGE approach
Schema-based storage via STORED-queries
– Datatype XML with methods based on XQuery
•
•
•
•
•
Query() – evaluates an XQuery and returns a value of type XML
Value() – evaluates an XQuery and returns a scalar SQL value
Exist() – returns true, if XQuery result is not empty
Modify() – updates a value of type XML
Nodes() – returns subtree of XML value
– Integrated Usage of SQL and XQuery
• Access to SQL data in XQuery via sql:column() and
sql:variable()
• Evaluation of XQuery expressions in SQL via XML methods from above
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13.4 SQL Server
• Native storage – table definition
– Schema registration
CREATE XML SCHEMA COLLECTION BuchXSD
AS '<?xml version="1.0"?>…'
– Table definition
CREATE TABLE Buch (
Id
INT PRIMARY KEY,
Inhalt XML BuchXSD)
)
– Insertion of an XML document from a file
INSERT INTO Buch
SELECT 1, xCol
FROM (SELECT *
FROM OPENROWSET
(BULK 'C:\XMLDIR\buch1.xml', SINGLE_BLOB) AS xCol)
AS R(xCol)
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13.4 SQL Server
• Native storage – SQL/XML queries & updates
– Find all author elements from books whose first author is
"Gunter Saake"
SELECT Inhalt.query('//Autor') AS Autoren
FROM Buch
WHERE Inhalt.exist('/Buch[Autor[1] = "Gunter Saake"]') = 1
Autoren
<Autor>Gunter Saake</Autor><Autor>Ingo Schmitt</Autor>
<Autor>Can Türker</Autor>
<Autor>Gunter Saake</Autor><Autor>Kai-Uwe Sattler</Autor>
– Update the value of the attributes "City" from all those
publisher elements to "Zürich", where the publisher is "dpunkt"
UPDATE Buch
SET Inhalt.modify
('replace value of (//Verlag[. = "dpunkt"]/@Ort)[1]
with "Zürich"')
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13.4 SQL Server
• Native storage – indexing
– Definition of a primary XML indexes
CREATE PRIMARY XML INDEX Idx_Inhalt ON Buch (Inhalt)
• Creates clustered index with entries of form (ID, ORDPATH,TAG, NODETYPE,
VALUE, PATH_ID, ...)
• necessary in order to create secondary indexes
– Secondary XML index types:
PATH | PROPERTY | VALUE
• Path index (path, value)
• Property index (primary key, path, value)
• Value index (value, path)
– Definition of a secondary XML index:
CREATE XML INDEX Idx_Inhalt_Path ON Buch (Inhalt)
USING XML INDEX Idx Inhalt
FOR <Indextyp>
– Full text index is also supported:
CREATE FULLTEXT INDEX Idx_Inhalt_FT ON Buch (Inhalt)
KEY INDEX b
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13.4 SQL Server
• Model-based storage with EDGE
– Invocation of OPENXML without WITH claus creates EDGE
table
[Tür08]
Column
Datatype
Task
id
bigint
unique node id
parentid
bigint
parent node id
nodetype
int
distinguishes elements, attributes, comments
localname
nvarchar
tag
prefix
nvarchar
XML namespace prefix
namespaceuri
nvarchar
XML namespace URI
datatype
nvarchar
datatype (derived from DTD or XML schema)
prev
bigint
id of previous node (in document order)
text
ntext
node content
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13.4 SQL Server
• Model-based storage with EDGE
EXEC sp_xml_preparedocument @hdoc OUTPUT, @xmldoctext
INSERT INTO EDGE
SELECT *
FROMOpenXML (@hdoc, '', 0)
EXEC sp_xml_removedocument @hdocC
– EDGE table:
id
parent
nodetype
localname
prefix
namespaceuri
datatype
prev
text
0
NULL
1
book
NULL
NULL
NULL
NULL
NULL
6
3
#text
NULL
NULL
NULL
NULL
'Vossen'
...
17
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13.4 SQL Server
• Schema-based storage of STORED queries
– SQL extension with OPENXML
– OPENXML transforms XML contents into database tables
(shredding)
– OPENXML therefore offers possibility to implement STORED
queries
– Example for the realization of a STORED query:
EXEC sp_xml_preparedocument @hdoc OUTPUT, @xmldoctext
INSERT INTO book
SELECT *
FROM OpenXML (@hdoc, '//book/', 0) WITH
(
title
NVARCHAR(3000) ‘./title',
publisher NVARCHAR(200) ‘./publisher‘,
isbn
NVARCHAR(15)
‘./isbn‘
)
EXEC sp_xml_removedocument @hdoc
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13.4 SQL Server
• Mapping of databases to XML
– Variant 1: Standard transformation with SQL SELECT and FOR
XML clause
• FOR XML RAW: Transformation in ROW-XML elements and XML
attributes
• FOR XML AUTO:
– Semantically rich XML element names
– Foreign key relationships are transformed into hierarchies
• FOR XML EXPLICIT: User controls XML assembling through metadata
(EDGE)
– Variant 2: User defined XML view
• Use of a (available) XML schema
• Annotation of the schema with information about tables and columns
• Accesss from the application to the XML view via:
– IIS functionality
– ADO (ActiveX Data Objects) – middleware for DB access
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13.4 SQL Server
• Updates
– SQL Server does not offer functions to update XML documents
stored as CLOBs
• Results in heavy restrictions of text-based approach
– Updates for schema-based approach possible via so called
updategrams
• Builds on annotated XML schemas
• Updates are specified as an XML document
• New namespace:
xmlns:updg="urn:schemas-microsoft-com:xml-updategram"
– Element before: Definition of a previous state (to be modified)
– Element after:
Definition of the new state
• Different update operations through varying element contents
– Insert:
before element remains empty
– Delete:
after element remains empty
– Update:
both elements have non-empty contents
• Automatic execution of necessary database operations
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13.4 SQL Server
• Updates: updategram example
– Update of publisher information
<ROOT xmlns:updg="urn:schemas-microsoft-com:xml-updategram">
<updg:sync >
<updg:before>
<Buch>
<Titel> Objektdatenbanken </Titel>
<ISBN>3-8266-00258-7 </ISBN>
<Verlag> Thomson </Verlag>
</Buch>
</updg:before>
<updg:after>
<Buch>
<Titel> Objektdatenbanken </Titel>
<ISBN>3-8266-00258-7 </ISBN>
<Verlag> International Thomson Publishing </Verlag>
<Buch>
</updg:after>
</updg:sync>
</ROOT>
[Tür08]
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13.4 SQL Server
• Summary SQL Server XML support
[Tür08]
XML storage model
Relational
Schema definition
inline DTD or XML schema
Storage type
Native: XML column
text-based: CLOB column
modelbased: with OPENXML
user-defined schema-based: with OPENXML-STORED queries
Mapping DB XML
Automatically: FOR XML clause
user-defined: XSD annotations
XML data type
Available
Value index
Available
Full text index
No XML specific functions
Path index
Available
Queries
SQl extensions (query and value not compatible with
SQL/XML), XQuery
Manipulation
XML method modify with updategrams
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13. Systems
13.1 Introduction
13.2 Oracle
13.3 DB2
13.4 SQL Server
13.5 Tamino
13.6 Summary
13.X Overview and References
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13.5 Tamino
• Architecture
[Tür08]
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13.5 Tamino
• Architecture (2)
XML Output
Data from external
sources and/or
internal data storage
[Tür08]
Query (URL)
XML Objects, DTDs
Data to external
sources and/or
internal data storage
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13.5 Tamino
• Storage structures: Mapping of XML
– Tamino uses "native" storage structures for XML data
– Native storage is supplemented with diverse classical index types
• B-Tree index
• Full text index
• Path index
– Storage alternatives:
• Storage of well-formed XML documents without schema
• Storage of valid XML documents
– Annotation of schema definition with storage alternatives
– Storage hierarchy:
•
•
•
•
[Tür08]
Tier 1: Tamino
Tier 2: Collection
Tier 3: Document type (defined by set of XML schema definitions)
Tier 4: document instance
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13.5 Tamino
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns:tsd="namespaces.softwareag.com/tamino/TaminoSchemaDefinition">
<xs:annotation> <xs:appinfo>
<tsd:schemaInfo name="book">
<tsd:collection name="books"></tsd:collection>
<tsd:doctype name="book">
<tsd:logical> <tsd:content>open<tsd:content></tsd:logical>
</tsd:doctype>
</tsd:schemaInfo>
</xs:appinfo> </xs:annotation>
<xs:element name = "book">
<xs:complexType> <xs:sequence>
<xs:element name = "title" type = "xs:string"></xs:element>
…
<xs:element name = "summary" type = "xs:string">
<xs:annotation> <xs:appinfo>
<tsd:elementInfo>
<tsd:physical> <tsd:native>
<tsd:index> <tsd:text></tsd:text> </tsd:index>
</tsd:native> </tsd:physical>
</tsd:elementInfo>
</xs:appinfo> </xs:annotation>
</xs:element>
</xs:sequence> </xs:complexType>
</xs:element>
Storage:
Example schema
with annotations
for text index
[Tür08]
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13.5 Tamino
• Queries
– Access possibilities
• Program controlled, e.g. via DCOM components
• Ad-hoc queries with X-Plorer query tool
• "Interactive Interface"
– Supported query languages
• XPath 1.0 dialect with extensions for text search (also possible without
index)
– Containedness (~=)
/Buch[Titel ~= "Datenmodelle"]/Beschreibung
– Wildcard character (*)
/*[. ~= "*XML*"]
– Consideration of context (NEAR)
/*[/Autor ~= "Gunter" NEAR "Saake"]
• XQuery dialect
[Tür08]
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13.5 Tamino
• Updates
– Operations
• Delete:
UPDATE DELETE $buch//Verlag[@Ort="Zürich"]/@Ort
• Insert:
UPDATE INSERT <Preis Waehrung="EUR">35</Preis>
INTO $buch[@ISBN="3-8266-0258-7"]
• Replace:
UPDATE REPLACE $buch//Verlag[@Ort="Zürich"]/@Ort
WITH ATTRIBUTE Ort {"Wiesbaden"}
[Tür08]
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13.5 Tamino
• Indexing
– Classical indexes for data
• Numbers and strings
– Text indexes for document centric parts
• With wildcards
– Structure index
• Full
• Condensed
– Combined index
• Multiple elements and attributes, even on different levels
– Multi path index
• Different paths indexed together
– Reference index
• Hierarchy aware index
[Tür08]
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13.5 Tamino
• Summary Tamino
[Tür08]
Native
Relational
Schema definition
Validation possible
Storage type
Model-based
Mapping DB XML
Native
XML data type
Available
Value index
Available
Full text index
Available
Path index
Available
Queries
Tamino X-Query (with extensions and small
differences compared to W3C XQuery)
Full text search
Supported
Manipulation
Supported
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13. Systems
13.1 Introduction
13.2 Oracle
13.3 DB2
13.4 SQL Server
13.5 Tamino
13.6 Summary
13.X Overview and References
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13.5 Summary
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13.6 Overview
Introduction XML Basics Schema definition XML query languages I Mapping relational data
to XML 6. SQL/XML 7. XML processing 1.
2.
3.
4.
5.
8. XML query languages II –
XQuery Data Model 9. XML query languages III
– XQuery 10. XML storage I –
Overview
11. XML storage II 12. Updates 13. Systems XML Databases – Silke Eckstein – Institut für Informationssysteme – TU Braunschweig
62
13.6 References
• "XML und Datenbanken" [Tür08]
– Can Türker
– Lecture, University of Zurich, 2008
• "XML und Datenbanken" [KM03]
– M. Klettke, H. Meier
– dpunkt.verlag, 2003
• " DB2 9 pureXML Guide" [IBM06a]
– IBM
– December 2006
• "DB2 Version 9. XML Guide" [IBM06b]
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Questions, Ideas, Comments
• Now, or ...
• Room:
IZ 232
• Office our:
Tuesday, 12:30 – 13:30 Uhr
or on appointment
• Email:
[email protected]
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