microsoft ado net entity framework step by step code

... Trang 1106 Microsoft ADO NET 4 Step by StepSummary This chapter introduced two ADO.NET features that enhance its core functionality: aggre-gates ... is even easier because ADO.NET will guess at the correct structure of the data even if you don’t provide table design guidance Trang 3108 Microsoft ADO NET 4 Step by StepWriting XML To generate ... the row-level tag instead <Customer ID="1"> Trang 9114 Microsoft ADO NET 4 Step by StepThis is accomplished by setting the DataColumn.ColumnMapping property for the relevant column

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... 116 Microsoft ADO.NET 4 Step by Step Generating XML from a DataSet : Visual Basic 1. Open the “Chapter 7 VB” project ... those chapters are similar to those used when writing LINQ queries for XML data. 118 Microsoft ADO.NET 4 Step by Step Chapter 7 Quick Reference To Do This Export a DataSet to a file as XML Create ... XML-based attribute Set the DataColumn.ColumnMapping property to MappingType. Attribute. Microsoft ADO.NET 4 Step by Step 119 Part II Connecting to External Data Sources Chapter 8: Establishing External

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... management between ADO.NET and external data sources. Note ADO.NET includes an “Entity Client” provider that enables provider-like functionality to the new ADO.NET Entity Framework system. ... 126 Microsoft ADO.NET 4 Step by Step The .NET Framework also includes string builders for OLE DB (System.Data.OleDb.OleDb ... database with ADO.NET requires three components: an active SQL Server database, an instance of SqlClient.SqlConne ction, and a valid connection string. 128 Microsoft ADO.NET 4 Step by Step Creating

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... single query You can generate them by sending a batch of two or more semicolon-delimited SELECT statements within a single SqlCommand object’s command text, or by executing a stored procedure that ... 6 Open the source code view for the StateBuilder form Locate the RefreshEverything routine Just after the “See if a custom state already exists” comment, add the following code: sqlText = "SELECT ... AddAbbreviation.Clear(); } if (stateReader != null) stateReader.Close(); This code uses the General.OpenReader function from step 5 to obtain a SqlDataReader instance built from a SQL statement (sqlText)

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... needed, and adding it to the SqlCommand.Parameters collection When you execute the command, ADO.NET passes both the placeholder-laden SQL text and the parameter collection to the database for ... require specific preci-sion and scale values Use these properties to configure the data from ADO.NET’s point of view ■ ■ Size Similar to Precision and Scale, Size is commonly used for text and ... builder.InitialCatalog = "StepSample"; builder.IntegratedSecurity = true; Adjust these statements as needed to provide access to your own test database 3 Open the code for the RenameCustomer

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... shows these components working on a single database table, Customer. 170 Microsoft ADO.NET 4 Step by Step Database ADO.NET Customer DataAdapter SELECT Fill Update INSERT UPDATE DELETE DataReader ... 166 Microsoft ADO.NET 4 Step by Step 4. Just after the “Read the next set, which contains the orders” comment, add the follow- ing code: customerReader.NextResult() ... of DataSet. 174 Microsoft ADO.NET 4 Step by Step C# DataSet targetSet = new DataSet(); SqlDataAdapter workAdapter = new SqlDataAdapter( "SELECT * FROM Customer ORDER BY LastName",

Ngày tải lên: 05/07/2014, 19:20

... implementation, and be aware of changes to ADO.NET in future releases that might affect your use of such statements. Using Local Transactions ADO.NET includes support for transactions with a ... conflicts ADO.NET, with its focus on disconnected data processing, uses optimistic concurrency Unfortunately, this method leaves some applications open to data conflicts of the type expe-rienced by ... versiontrack = @OriginalRowVersion Note Some database platforms support statements that let you sidestep ADO.NET’s preference for optimistic concurrency The Oracle SELECT statement, for example, includes

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... transaction’s overall changes. 204 Microsoft ADO.NET 4 Step by Step Using Distributed Transactions The .NET Framework includes support for distributed transactions through the Microsoft Distributed Transaction ... rolled back by the // database because it did not get a commit order. MessageBox.Show("Error undoing the changes: " + ex2.Message); } } 198 Microsoft ADO.NET 4 Step by Step Visual ... any of these three lines raises an exception in the subsequent catch block. 200 Microsoft ADO.NET 4 Step by Step 7. Just after the “Do a rollback instead” comment, within the inner try block,

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... method. Microsoft ADO.NET 4 Step by Step 211 Part III Entity Framework Chapter 13: Introducing the Entity Framework Chapter 14: Visualizing Data Models Chapter 15: Querying Data in the Framework ... following line: envelope.Complete() This method call commits the entire transaction. 208 Microsoft ADO.NET 4 Step by Step 4. Run the program. In the local-transaction sample earlier in this chapter, ... 206 Microsoft ADO.NET 4 Step by Step Processing with a Distributed Transaction: C# Note This exercise uses the “Chapter

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... 4<EntityContainer Name="StepSampleConnection" LazyLoadingEnabled="true"> <EntitySet Name="Customers" EntityType="StepByStep.Customer" /> <EntitySet ... Classes generated by the Framework implement in code the entities, properties, and associations defined in the model Understanding the Entity Framework’s Layers In the Entity Framework, you define ... an entity con-tainer, the outermost conceptual construct within the Entity Framework When writing code that interacts with entities, you will always start by creating an instance of an entity

Ngày tải lên: 05/07/2014, 19:20

... two types of code-generation items for use with Entity Framework models: ■ ■ ADO.NET EntityObject Generator This is the default type, and the same type Visual Studio uses internally by default ... To add a custom code generator to your project, use Visual Studio’s Project | Add New Item menu command, and choose either ADO.NET EntityObject Generator or ADO.NET Self-Tracking EntityObject Generator ... search for “Generated Code Overview” within the Visual Studio online help Summary This chapter continued the overview of the Entity Framework by introducing the ADO.NET Entity Data Model Designer

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... SELECT, FROM, WHERE, GROUP BY, and ORDER BY clauses. SELECT list-of-fields FROM one-or-more-tables WHERE Boolean-expression GROUP BY aggregate-grouping-fields ORDER BY sort-by-fields As with standard ... T-SQL focuses on the logical tables and rows in the database Even when an Entity Framework model targets a SQL Server database, Entity SQL queries focus on the data as expressed through the conceptual model Writing Basic Queries Entity SQL selection ... updates are needed, the standard Entity Framework tools take over ■ ■ None of the batch query or stored procedure functionality found in T-SQL is available in Entity SQL Entity SQL does include support

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... included with the Entity Framework, this is a small omission But if you need to push entity data into a standard ADO.NET structure, you will have to do so manually When using the EntityCommand.ExecuteReader ... an Entity Data Model The key classes for the EntityClient provider appear in the System.Data EntityClient namespace. Using the EntityClient provider to query data covers the same general steps ... and then ultimately through a provider such as the SQL Server ADO.NET provider The Entity Framework hosts its own data provider: the EntityClient provider This provider exposes much of the same

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... are two Framework base classes (introduced earlier in this chapter) that act as collections for named or anonymous entity types. 280 Microsoft ADO.NET 4 Step by Step Consider this simple Entity ... located the entity by ID. 284 Microsoft ADO.NET 4 Step by Step Using Query Builder Methods: Visual Basic Note This exercise continues the previous exercise in this chapter. 1. Open the source code ... argument and returns only those instances that are found in both. 282 Microsoft ADO.NET 4 Step by Step Query Builder Method Entity SQL Equivalent Description Except EXCEPT Returns all records

Ngày tải lên: 05/07/2014, 19:20