Create Better Spreadsheets, Faster in C#.net

Develop code128b in C#.net Create Better Spreadsheets, Faster

Service Broker brings the advantages of asynchronous execution and reliable messaging to SQL Server applications . Service Broker s message ordering, correlation, and activation features are unequaled by any messaging system . When combined with CLR integration, database mirroring, and the new XML features, Service Broker makes SQL Server 2008 a viable platform for building database applications and services that offer unprecedented levels of reliability and fault tolerance .

' GetEnvInfo Procedure ' Returns environment info in tabular format <SqlProcedure()> _ Public Shared Sub GetEnvInfo() ' Create a record - object representation of a row ' Include the metadata for the SQL table Dim record As New SqlDataRecord( _ New SqlMetaData("EnvProperty", SqlDbType.NVarChar, 20), _ New SqlMetaData("Value", SqlDbType.NVarChar, 256)) ' Marks the beginning of the result set to be sent back to the client ' The record parameter is used to construct the metadata for ' the result set

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This code is shorter and simpler, and the optimizer generates a more efficient plan for it, as you will notice if you request the graphical execution plan in SSMS. You will find in the execution plan that the Customers table is scanned only once, and through that scan, the query processor accesses all the customer attributes it needs. This plan reports half the estimated execution cost of the previous one. In practice, if you compare the two solutions against larger tables, you will find that the performance difference is substantially higher. Alas, the UPDATE with a join technique is nonstandard. ANSI supports syntax called row value constructors that allows you to simplify queries like the one just shown. This syntax allows you to specify vectors of attributes and expressions and eliminates the need to issue a subquery for each attribute separately. The following example shows this syntax: UPDATE dbo.Orders SET (ShipCountry, ShipRegion, ShipCity) = (SELECT Country, Region, City FROM dbo.Customers AS C WHERE C.CustomerID = dbo.Orders.CustomerID); WHERE C.Country = 'USA';

1. From Computer2, log on to Domain1 as Administrator. Remember to specify the password you originally assigned to the Administrator account on Computer1.

DECLARE @T1 TABLE(col1 INT); INSERT @T1 VALUES(1); SELECT * FROM @T1;

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Figure 6-6: The sample application sorts nodes by title and lastname. To generate the output shown in this figure, I made use of an XPath iterator to visit all the nodes and their own subtrees. We'll examine this code in detail in the section "Visiting the Selected Nodes," on page 286, but first we'll take a look at the internal layout of the XML document classes the navigator relies on. XPath Data Stores As mentioned, an XPath navigator works on top of an ad hoc document class. The .NET Framework provides three XPath-enabled classes: XmlPathDocument, XmlDocument, and XmlDataDocument. These classes have in common the IXPathNavigable interface. In theory, each .NET Framework class can become XPath-enabled. In practice, however, only a subset of classes is a good candidate. In the first place, the class must act as the in-memory repository of some sort of content. Second, this content must be, or must be exposed as, XML. When these two prerequisites are met, classes can reasonably implement the IXPathNavigable interface and create their own navigators. An XPath navigator is always class-specific and is built by inheriting from the abstract class XPathNavigator. Although in practice you always use navigators through the generic reference type of XPathNavigator, each class has its own navigator object. Table 6-9 lists these internal, undocumented classes; they are programmatically unaccessible, and often each is implemented in a different way. Despite this complexity, however, the classes' application-level programming interface is common and is based on their base class XPathNavigator. Table 6-9: Document-Specific Navigator Classes Document Class Corresponding Internal Navigator Class XPathDocument System.Xml.XPath.XPathDocumentNavigator XmlDocument System.Xml.DocumentXPathNavigator XmlDataDocument System.Xml.DataDocumentXPathNavigator The document-specific navigator exploits the internal layout of the document class to provide the navigation API. A document-specific navigator can also have new methods and properties that make sense to a particular implementation. In this case, however, 229

The cgi library is a part of the standard library, so it comes with Ruby by default. To use it, you only need to place this line near the start of your program: require 'cgi'

Using the same path notation, the Joomla License Guidelines article that s included in the sample data could be located via a path like this:

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