Despite the excitement surrounding XML, it is important to note that most operational business data, even for new Web-based applications, continues to be stored in relational DBMSs. This is unlikely to change in the foreseeable future because of their reliability, scalability, tools, and performance. Consequently, if XML is to fulfil its potential, some mechanism is required to publish relational data in the form of XML documents. The SQL:2003 standard has defined extensions to SQL to enable the publication of XML, commonly referred to as SQL/XML. Discuss in detail these extensions.
What will be an ideal response?
SQL/XML contains:
? a new native XML data type, XML, which allows XML documents to be treated as
relational values in columns of tables, attributes in user-defined types, variables, and
parameters to functions;
? a set of operators for the type:
? XMLELEMENT, to generate an XML value with a single element as a child of
its root item. The element can have zero or more attributes specified using an
XMLATTRIBUTES subclause.
? XMLFOREST, to generate an XML value with a list of elements as children of
a root item.
? XMLCONCAT, to concatenate a list of XML values.
? XMLPARSE, to perform a non-validating parse of a character string to produce
an XML value.
? XMLROOT, to create an XML value by modifying the properties of the root
item of another XML value.
? XMLCOMMENT, to generate an XML comment.
? XMLPI, to generate an XML processing instruction.
? XMLSERIALIZE, to generate a character or binary string from an XML value;
? XMLAGG, an aggregate function, to generate a forest of elements from a
collection of elements.
? an implicit set of mappings from relational data to XML. The mapping may take as its
source an individual table, all the tables in a particular schema, or all the tables in a given
catalog. The standard does not specify a syntax for the mapping; instead it is provided for
use by applications and as a reference for other standards. The mapping produces two
XML documents: one that contains the mapped table data and the other that contains an
XML Schema describing the first document.
You might also like to view...
A(n) __________ is a potential for violation of security, which exists when there is a circumstance, capability, action or event that could breach security and cause harm.
A) threat B) attack C) risk D) attack vector
________ is a searchable collection of royalty-free images provided by Microsoft
Fill in the blank(s) with correct word
Which OSPF network statement will correctly include all the interfaces on a device that begin with an IP address of 172.16.0.0/16?
A) network 0.0.16.172 255.255.0.0 area 0 B) network 172.16.0.0 0.0.255.255 area 0 C) network 172.16.0.0 255.255.0.0 area 0 D) network 0.0.16.172 0.0.255.255 area 0
Fred finds a packet that his protocol analyzer shows with both PSH and URG set. What type of packet is he looking at, and what do the flags mean?
A. A UDP packet; PSH and URG are used to indicate that the data should be sent at high speed B. A TCP packet; PSH and URG are used to clear the buffer and indicate that the data is urgent C. A TCP packet; PSH and URG are used to preset the header and indicate that the speed of the network is unregulated D. A UDP packet; PSH and URG are used to indicate that the UDP buffer should be cleared and that the data is urgent