Programmatically using ado. net and xml – codeproject

ADO.NET can be used as a powerful XML middleware. Data recovery on ssd Although coming from ADO, it has been entirely redesigned for a better support for Web applications. Database query tools A main feature of ADO.NET is its disconnected recordsets, known as DataSet. Database 2000 It acts as a feature-rich in-memory database or data cache. Database business rules In other words, it does not maintain any database server cursors. Iphone 5 data recovery All recordset’s database characteristics are available in DataSet, such as sorting, paging, filtered views, relations, indexing, and primary/foreign keys. Native support for XML is another principal feature for ADO.NET. Database implementation In native mode, record tables are stored as XML documents where schema and data are treated as distinct and replaceable elements. Raid 1 data recovery software It is quite different from ADO. Seagate data recovery The ADO native storage format for a recordset is the Advanced Data Table Gram (ADTG) file format, which is a proprietary, binary schema that represents a recordset’s in-memory image. Database report The DataSet objects in ADO.NET can load its data from variant sources: a database server, a local or remote XML file and any accessible system resources. Data recovery specialist Once the data is loaded, they can be either treated as a record table or a virtual XML document. Data recovery iphone 6 We principally discuss the latter. Database building Now, I will give you several use cases. Data recovery top 10 Each use case is a standalone unit test which can be run under NUnit. Database hosting So you should install a latest version of NUnit. Data recovery best More information about its installation and usage can be found here.Before executing these examples, you should also setup an ODBC connection for the database with the following steps: With ADO.NET, we can easily build a virtual XML document on top of recordset tables. Data recovery program Its root element has exactly the same name as the DataSet object. 7 data recovery 94fbr Tables in the DataSet object present as child nodes of the root element. Database languages For example, there is a DataSet named “ XmlDb”. Database ranking When it is transformed into XML document, the name of its root element will be “ XmlDb” (refer to Figure 2). Data recovery youtube All rows in the table “Customers” will be mapped to a unique child node of the root element, whose node name matches the table name “Customers”. 911 database In Figure 2, “CustomID”, “CompanyName”, etc. Data recovery download are fields of the table “Customers”. Data recovery after factory reset When they are transformed into XML, they present as child nodes of “ Customers”. Database schema design Their node name will be the same as the field name and node value will be the value of that field. Output: < XmlDb > < Customers > < CustomerID >ALFKI < /CustomerID > < CompanyName >Alfreds Futterkiste < /CompanyName > < ContactName >Maria Anders < /ContactName > < ContactTitle >Sales Representative < /ContactTitle > < Address >Obere Str. Database uml 57 < /Address > < City >Berlin < /City > < PostalCode >12209 < /PostalCode > < Country >Germany < /Country > < Phone >030-0074321 < /Phone > < Fax >030-0076545 < /Fax > < /Customers > Entity-Relationship model is a long-tested approach to map the real world to database structure. Data recovery ntfs Relationships are often represented as Master-Detail tables, which can be naturally transformed into XML parent/child nodes, with ADO.NET. Database error The Figure 3 shows you such a mapping: The key point to generate nested XML nodes is to setup a DataRelation object to link the master table and the detail table with the primary key and the foreign key. Database functions Like this: DataColumn primarykey = dataset.Tables[ ” Customers”].Columns[ ” CustomerID”]; Output: < XmlDb > < Customers > < CustomerID >ALFKI < /CustomerID > < CompanyName >Alfreds Futterkiste < /CompanyName > < ContactName >Maria Anders < /ContactName > < ContactTitle >Sales Representative < /ContactTitle > < Address >Obere Str. Top 10 data recovery 57 < /Address > < City >Berlin < /City > < PostalCode >12209 < /PostalCode > < Country >Germany < /Country > < Phone >030-0074321 < /Phone > < Fax >030-0076545 < /Fax > < Orders > < OrderID >10643 < /OrderID > < CustomerID >ALFKI < /CustomerID > < OrderDate >1995-09-25T00:00:00.0000000+02:00 < /OrderDate > < RequiredDate >1995-10-23T00:00:00.0000000+02:00 < /RequiredDate > < ShippedDate >1995-10-03T00:00:00.0000000+02:00 < /ShippedDate > < Freight >29.4600 < /Freight > < ShipName >Alfreds Futterkiste < /ShipName > < ShipAddress >Obere Str. Database job titles 57 < /ShipAddress > < ShipCity >Berlin < /ShipCity > < ShipPostalCode >12209 < /ShipPostalCode > < ShipCountry >Germany < /ShipCountry > < /Orders > < Orders > < OrderID >10692 < /OrderID > < CustomerID >ALFKI < /CustomerID > < OrderDate >1995-11-03T00:00:00.0000000+01:00 < /OrderDate > < RequiredDate >1995-12-01T00:00:00.0000000+01:00 < /RequiredDate > < ShippedDate >1995-11-13T00:00:00.0000000+01:00 < /ShippedDate > < Freight >61.0200 < /Freight > < ShipName >Alfred’s Futterkiste < /ShipName > < ShipAddress >Obere Str. Data recovery linux live cd 57 < /ShipAddress > < ShipCity >Berlin < /ShipCity > < ShipPostalCode >12209 < /ShipPostalCode > < ShipCountry >Germany < /ShipCountry > < /Orders > < /Customers > .NET Framework implements all DOM interfaces in its System.Xml namespace. S pombe database Moreover, it has integrated XPath in the XmlNode level as an extension to DOM. Database usa So, once a virtual XML document is built, it can be queried with XPath immediately. Data recovery pro license key For example, in last section, we have created an XML document which represents “Customers” and their correspondent “Orders”. Data recovery on android Now, we want to find out all customers in Berlin and have asked to ship the ordered products to Germany. Icare data recovery 94fbr We can perform such a search on the XML document with one line of code: XmlNodeList nodeList = Output: < Results > < Orders > < OrderID >10643 < /OrderID > < CustomerID >ALFKI < /CustomerID > < OrderDate >1995-09-25T00:00:00.0000000+02:00 < /OrderDate > < RequiredDate >1995-10-23T00:00:00.0000000+02:00 < /RequiredDate > < ShippedDate >1995-10-03T00:00:00.0000000+02:00 < /ShippedDate > < Freight >29.4600 < /Freight > < ShipName >Alfreds Futterkiste < /ShipName > < ShipAddress >Obere Str. Image database 57 < /ShipAddress > < ShipCity >Berlin < /ShipCity > < ShipPostalCode >12209 < /ShipPostalCode > < ShipCountry >Germany < /ShipCountry > < /Orders > < Orders > < OrderID >10692 < /OrderID > < CustomerID >ALFKI < /CustomerID > < OrderDate >1995-11-03T00:00:00.0000000+01:00 < /OrderDate > < RequiredDate >1995-12-01T00:00:00.0000000+01:00 < /RequiredDate > < ShippedDate >1995-11-13T00:00:00.0000000+01:00 < /ShippedDate > < Freight >61.0200 < /Freight > < ShipName >Alfred’s Futterkiste < /ShipName > < ShipAddress >Obere Str. Database web application 57 < /ShipAddress > < ShipCity >Berlin < /ShipCity > < ShipPostalCode >12209 < /ShipPostalCode > < ShipCountry >Germany < /ShipCountry > < /Orders > Although accessing DataSet with XML provides some unique advantages, we still need to obtain some complemental information about the data. Database graphic For example, ADO.NET marks every DataRow with its current state, namely Added, Deleted, Detached, Modified, and Unchanged. In databases a category of data is called a These states are important when we perform update to the data source. Database wordpress Fortunately, XmlDataDocument provides a useful method to help us get correspondent DataRow from the XmlElement. Note 2 data recovery Once we get the DataRow, its current state can be obtained through its property RowState: DataRow row = xmlDataDocument.GetRowFromElement(xmlElement); It is quite attractive to convert the content in DataSet to variant output formats, such as HTM
L/XHTML, WAP, PDF, SVG etc. Tally erp 9 data recovery The .NET Framework provides perfect support for XSLT which facilitates such kinds of transformation. Database erd More information about XSLT can be found here. Now, let’s suppose we want to generate a simple report about the order details of the ten most expensive products. Database google docs Following the previous several sections, we can easily build a virtual nested XML document from the “Products” and “OrderDetails” tables. Database 5500 Then we create an XSTL file like this: < xsl:stylesheet xmlns:xsl =" http://www.w3.org/1999/XSL/Transform" version =" 1.0" > < xsl:template match =" /" > < HTML > < BODY > < TABLE BORDER =" 0" cellspacing =" 3" cellpadding =" 8" > < TR bgcolor =" #FFCC00" > < TD >Product Name < /TD > < TD >Price < /TD > < TD >Discount < /TD > < TD >Quantity < /TD > < TD >Total < /TD > < /TR > < xsl:apply-templates select =" XmlDb/Products[position() < 10]" > < xsl:sort select =" UnitPrice" order =" descending" data-type = " number" / > < /xsl:apply-templates > < /TABLE > < /BODY > < /HTML > < /xsl:template > < xsl:decimal-format name =" us" decimal-separator =' .' grouping-separator =' ,' / > < xsl:template match =" XmlDb/Products[position() < 10]" > < TR > < xsl:if test =" position() mod 2 = 0" > < xsl:attribute name =" bgcolor" >#EEEEEE < /xsl:attribute > < /xsl:if > < xsl:if test =" position() mod 2 = 1" > < xsl:attribute name =" bgcolor" >#AAAAAA < /xsl:attribute > < /xsl:if > < TD > < xsl:value-of select =" ProductName" / > < /TD > < TD > < xsl:value-of select =" format-number(UnitPrice, '#.00', 'us')" / >$ < /TD > < xsl:if test =" number(OrderDetails/Discount) != 0" > < TD >– < xsl:value-of select =" number(OrderDetails/Discount)*100" / >% < /TD > < /xsl:if > < xsl:if test =" number(OrderDetails/Discount) = 0" > < TD >—– < /TD > < /xsl:if > < TD > < xsl:value-of select =" OrderDetails/Quantity" / > < /TD > < TD > < xsl:value-of select =" number(UnitPrice)*number(OrderDetails/Quantity)* Standard XPath is not powerful enough to be a database query language, e.g.: it lacks the DateTime related functions. Data recovery kit Fortunately, it could be enhanced with customized XPath functions. Database meaning Mr. Gale database Prajakta Joshi has published a very comprehensive article on this topic in MSDN. Data recovery pc But his approach is too complex to follow. Data recovery easeus You should manually point out the function name, arguments number and their types, return type for every customized function, etc. Top 10 data recovery software It is not so flexible to add new XPath functions and is hard to maintain. Database oracle Now, let's use the Reflection mechanism in .NET Framework to simplify this process (refer to Figure 5). All customized functions can only present as static methods in the XmlDbXPathFunctions class. Data recovery services reviews Once XPathExpress requires XsltContext to ResolveFunction(). Database 12c new features The XsltContext creates an XmlDbXPathFunctionWrapper object which implements the IXsltContextFunction interface. Database lyrics A function name and required argument types will be passed to its constructor. Database 360 In the constructor, XmlDbXPathFunctionWrapper tries to find a best-fit static method in the XmlDbXPathFunctions class. Database architect salary Then XPathExpression call the Invoke() method of XmlDbXPathFunctionWrapper, which will invoke the real correspondent method in the XmlDbXPathFunctions class and return the result. This is a very flexible approach to extend the XPath. Database administrator job description If you want to add your own function to XPath execution context, you just need to write a static method in the XmlDbXPathFunctions class. Data recovery app The new function will be detected automatically. Some useful DateTime functions have already been added. R database connection Now you can extract the year, month, day, hour, minute, second, ticks form a DateTime XmlNode. Database weak entity It is quite helpful when you try to filter the XmlNode set with the DateTime information. Data recovery vancouver For example: "//Orders[ex:year(string(ShippedDate)) = 1995 and ex:month(string(ShippedDate)) <= 3]" will seek all orders shipped in the first quarter in the year of 1995. Level 3 data recovery [Test] public void XPathExtension() Output: < Results > < ShippedDate >1995-01-03T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-01-02T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-02-16T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-01-13T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-01-16T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-02-10T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-02-10T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-02-09T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-03-02T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-02-27T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-02-27T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-03-03T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-03-27T00:00:00.0000000+02:00 < /ShippedDate > < ShippedDate >1995-02-27T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-03-17T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-03-09T00:00:00.0000000+01:00 < /ShippedDate > < ShippedDate >1995-03-31T00:00:00.0000000+02:00 < /ShippedDate > If you need some special XPath functions, just add them as static methods into the XmlDbXPathExtensionFunctions class.


Database blob These static methods will be found automatically and be applied to your XPath query. Database examples Really simple, isn’t it? Conclusion Treating a database as a large virtual XML document with ADO.NET is not always a good idea. Database knowledge It demands more memory, and its performance could be a big problem in the case of complex and enormous databases. H2 database But for relatively small projects, it works perfectly and might save a lot of time for you. Nexus 5 data recovery Anyways, you could optimize the code above to make it meet your requirements. I’m trying to generate an XML schema using the dataset method WriteXmlSchema. Data recovery uk The dataset contains four tables and several relations as shown below. Database collation The CompanyDataTable is a parent table which has two child tables: CompanyAddressTable and CategoryDataTable. Database yugioh Whereas the relationship with the first child table is one-to-one, the relationship with the second table is one-to-many (a single category can be linke to multiple companies). Top 10 data recovery software free Setting the nested property to true for the first relationship generates the XML schema with no problem, but enabling the nested property of the second relation pops up the following error: “A child row has multiple parents.”. Data recovery vancouver bc Does any one know if there is a way that I can have this relation included in my schema using WriteXMLSchema or do I have to create it my own using XMLElement?

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