Download Persisting Result Sets as XML Data Files

Persisting Result Sets as XML Data Files
DataDirect Connect® Series ODBC Drivers
Introduction
DataDirect Connect® Series ODBC drivers (DataDirect Connect for ODBC and
DataDirect Connect64 for ODBC) include a feature that enables you to retrieve
result sets from a relational database (such as Oracle, Informix, DB2, or
Sybase) and store the result sets as XML data files (see following figure).
This can be accomplished by simply adding one or two lines of code to
existing ODBC applications.
ODBC
Application
DataDirect
Connect
for ODBC
Driver
Result Set
XML
Data File
Result Set
Relational
Database
DataDirect Connect for ODBC Drivers are currently the only ODBC drivers on
the market that can persist result sets as XML data files.
Benefits of Using DataDirect Connect ® Series ODBC Drivers to
Persist Data as XML
The ability to persist result sets as XML data files helps you take advantage
of XML faster as you adopt advanced B2B and B2C business processes on
the Web. DataDirect Technologies provides a simple way for you to use
existing data and publish it on the Web. You do not have to replicate the data
or manually reformat it—you just add one or two lines of code to your
existing ODBC application and an XML data file is created.
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XML allows you to use the power of the Web to provide up-to-date
information to your colleagues within the same organization, your outside
partners, and your customers. For example, instead of e-mailing a textformatted report to sales representatives in the field, you can publish daily
sales information in an XML report on a secure Web page, which is
accessible to a PC, a laptop, or a handheld device.
Creating XML from data stored in a relational database offers a way for you
to:
Quickly publish information (such as up-to-date price lists or current
inventory totals) to the Web
Allow customers to interact with the data you publish on the Web
Scenario
In this scenario, a wholesaler decides to provide an online catalog over the
Web. The wholesaler chooses XML for the format of the catalog because
XML provides semantics to the online catalog information that will allow the
customer to do business with the wholesaler online.
The wholesaler's catalog information is stored natively in an Oracle relational
database inside the wholesaler's Internet firewall. Through an ODBC
application using a DataDirect Connect Series ODBC Oracle driver, the
wholesaler retrieves the data from the relational database and publishes that
information to the Web Server as an XML data file in the form of an online
catalog. To do this, the ODBC application issues a SQL Select statement, for
example:
SQLExecDirect (hstmt, "Select ITEM_NO, PRICE,
DESCRIPTION, PHOTO FROM ALL_STOCK ORDER BY 3", SQL_NTS)
Once the wholesaler has published the catalog on the Web as an XML data
file, the customer can view the catalog using any XML-enabled browser.
More important, customers can deal with the wholesaler more efficiently by
using applications to interact with the catalog just as if they had direct access
to the wholesaler’s relational database.
The wholesaler develops and distributes to his customers an ODBC
application that:
Connects to a URL that specifies the wholesaler’s XML catalog
Checks the price and availability of any item in the wholesaler’s catalog
Places the order if the item is in stock
In addition, the customer could develop custom applications to interact with
the wholesaler’s catalog, applications that fit the exact needs of the
customer.
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In this scenario, both the wholesaler and consumer benefit by the
wholesaler’s catalog being published to the Web using XML. And, DataDirect
Connect Series ODBC drivers provide a way to persist data easily from a
relational database to XML.
Implementing XML Persistence
This section provides step-by-step instructions for implementing XML
persistence in an ODBC application using a DataDirect Connect for ODBC
Driver.
The ODBC application must:
1. Turn on STATIC cursors. For example:
SQLSetStmtAttr (hstmt, SQL_ATTR_CURSOR_TYPE,
SQL_CURSOR_STATIC, SQL_IS_INTEGER)
NOTE: A result set can be persisted as an XML data file only if the result set
is generated using STATIC cursors.
2. Execute a SQL statement. For example:
SQLExecDirect (hstmt, "Select * from GTABLE", SQL_NTS)
3. Persist the result set as an XML data file. For example:
SQLSetStmtAttr (hstmt, SQL_PERSIST_AS_XML,
"c:\temp\GTABLE.XML", SQL_NTS)
NOTE: A statement attribute is available to support XML persistence,
SQL_PERSIST_AS_XML. A client application must call SQLSetStmtAttr with
this attribute as an argument. See the following table for the definition of valid
arguments for SQLSetStmtAttr.
D A T A D I R E C T
Argument
Definition
StatementHandle
The handle of the statement that contains the result
set to persist as XML.
Attribute
SQL_PERSIST_AS_XML. This statement attribute
can be found in the file qesqlext.h, which is installed
with the driver.
ValuePtr
Pointer to a URL that specifies the full path name of
the XML data file to be generated. The directory
specified in the path name must exist, and if the
specified file name exists, the file will be overwritten.
StringLength
The length of the string pointed to by ValuePtr or
SQL_NTS if ValuePtr points to a null terminated
string.
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An ODBC application can persist the data at any time that the statement is in
an executed or cursor-positioned state.
Summary
DataDirect Connect Series ODBC drivers include the ability to persist result
sets as XML data files for the leading databases: Oracle, Informix, DB2, and
Sybase. The benefit to you is that you can quickly publish information to the
Web and allow customers to interact with the data you publish. Currently,
DataDirect Technologies provides the only ODBC drivers on the market that
provide this functionality.
We welcome your feedback! Please send any comments concerning documentation, including
suggestions for other topics that you would like to see, to:
[email protected]
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FOR MORE INFORMATION
800-876-3101
DataDirect Technologies is focused on data access, enabling
software developers at both packaged software vendors and in
corporate IT departments to create better applications faster.
DataDirect Technologies offers the most comprehensive, proven
line of data connectivity components available anywhere.
Developers worldwide depend on DataDirect Technologies to
connect their applications to an unparalleled range of data
sources using standards-based interfaces such as ODBC, JDBC
and ADO.NET, as well as cutting-edge XML query technologies.
More than 250 leading independent software vendors and
thousands of enterprises rely on DataDirect Technologies to
simplify and streamline data connectivity. DataDirect
Technologies is an operating company of Progress Software
Corporation (Nasdaq: PRGS).
[email protected]
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reserved. DataDirect Connect is a registered trademark of
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