Data Types 1
All values that map to any of the SQL types binary, image, ntext, text, or varbinary must be marked in the schema as having that sql datatype. Otherwise, the updategram will not be able to generate a valid SQL query. Similarly, both monetary types money, smallmoney must be marked as having one of the XDR numeric types to be properly used, even though you could still have an attribute type unitprice, without either datatype. The XDR binary types bin.hex and bin.base6 4 are used when decoding...
Performing a Batch Update Via HTTP The WebRowSetUpdateServlet Class
The next step is to write a servlet that allows you to update the underlying data source via HTTP. This servlet will accept a remote WebRowSet's XML representation via HTTP POST and perform a batch update of the underlying data source. Note for this servlet to function properly, the RowSet.dtd file must be in the jakarta-tomcat bin directory so that the WebRowSet class can find it to validate the uploaded document. import javax.servlet. import javax.servlet.http. import java.io. import...
Data Types sqldatatype dttype sqlidprefix
Perhaps the trickiest problem in providing an XML view over SQL data is managing the vast differences between their type systems. XDR has a type system SQL has a different one. XPath has yet another. At the time of this writing, XSD and the XML Query Language are not yet finalized, but both will have their own different type systems. We will not cover the SQL type system in any depth. The sql datatype annotation exists mainly to allow updategrams to handle certain binary types and to improve...
Create and Edit Customer Accounts
Previously, we demonstrated how to post a template through an HTML form. This method is straightforward but presents all sorts of security risks. A better approach is to pass parameters to a server-side template that is completely under your control. Although we are only storing each Customer's name and favorite color, this technique obviously generalizes to larger sets of parameters. We first need a login new account page ch2 0_ex3 0.html lt TITLE gt Welcome to the Internet Lemonade Stand lt...
Improve the Schema
However, the schema ch2 0_ex2 6.xdr does not really represent the shape of our data. None of the elements are connected, even though several of the tables we have in the database are normally joined together. There are several different XML Views that could make sense for our data, but a customer-centric view is especially relevant. In this view, we list all our customers ordered by name, and the purchases made for each customer. In creating this view, we will also specify additional...
element and xml Directives
The element and xml directives produce element-centric XML rather than attribute-centric. For example, our ch14_ex06.sql example of the EXPLICIT section returned the following attribute-centric XML If we add the element directive to the column aliases in this example, the query will now look like this ch14_ex08.sql Customers.CustomerID as Cust 1 CustID element , Customers.ContactName as Cust 1 Contact element FROM Customers ORDER BY Cust 1 CustID element FOR XML EXPLICIT The XML returned by...
OPENXML Attributecentric and Elementcentric Mapping
By default, OPENXML assumes that each of the rowset columns maps to the samename attribute in the source XML i.e. attribute-centric mapping is the default . However, you can set the Flags parameter to an appropriate value to specify element-centric Flags 2 or mixed Flags 3 . If Flags is set to mixed, then attribute-centric mapping is first applied to the remaining rowset columns, followed by element-centric mapping, as shown in the following example. The lt Order gt element in the following...
Info Nvl
The lt xsl if gt instruction performs an action if a condition is true. There is no else branch if you need one, use lt xsl choose gt instead. lt xsl if gt has a mandatory test attribute which defines the condition to be tested, as an XPath expression whose result is automatically converted to a Boolean. The lt xsl if gt element contains a template body which is instantiated if and only if the condition is true. This example outputs a message containing the word errors unless there was only...