Is this page helpful? Yes No. Any additional feedback? Skip Submit. DataSet String. Gets the container for the component. Inherited from MarshalByValueComponent. Gets a value indicating whether the component is currently in design mode. Gets the list of event handlers that are attached to this component.
Gets or sets the locale information used to compare strings within the table. CreateDataReader DataTable[]. Dispose Boolean. Equals Object. Determines whether the specified object is equal to the current object. Inherited from Object. GetChanges DataRowState. Serves as the default hash function. GetService Type. HasChanges DataRowState. InferXmlSchema Stream, String[]. InferXmlSchema String, String[].
Merge DataRow[]. Merge DataSet. Merge DataSet, Boolean. Merge DataTable. OnRemoveRelation DataRelation. OnRemoveTable DataTable. RaisePropertyChanging String. ReadXml Stream. ReadXml String. ReadXml TextReader.
ReadXml XmlReader. ReadXmlSchema Stream. ReadXmlSchema String. ReadXmlSchema TextReader. ReadXmlSchema XmlReader. A Data Adapter contains a set of data commands and a database connection to fill the dataset and update a SQL Server database. Data Adapters form the bridge between a data source and a dataset. Data Adapters are designed depending on the specific data source.
The following table shows the Data Adapter classes with their data source. Its object contains a reference to a connection object. It is designed in a way that implicitly opens and closes the connection whenever required. It maintains the data in a DataSet object. The user can read the data if required from the dataset and write back the changes in a single batch to the database.
A Data Adapter supports mainly the following two methods: Fill The Fill method populates a dataset or a data table object with data from the database.
The Fill method leaves the connection in the same state as it encountered it before populating the data. If subsequent calls to the method for refreshing the data are required then the primary key information should be present. Update The Update method commits the changes back to the database. NET object and a data source. Tables[ "Emp" ];.
View All. Akash Bhimani Updated date Nov 03, Definition : ADO is a rich set of classes, interfaces, structures, and enumerated types that manage data access from various types of data stores.
The connection string is different for each of the various data providers available in. You can find a list of all the available providers for creating a connection in a table:. Add two buttons and a DataGridView control.
Change the text of the first button to sort by city and that of button2 to only select records in Mexico and add the code in form. Program: Design a simple Winform for accepting the details of Employee.
Using the connected architecture of ADO. NET, perform the following operations:. Program: Design a Simple Winform for accepting the details of an Employee. Program : Design a simple Winform for accepting the details of an Employee. I hope at the end of this article, you will understand the Architecture of DataSet in.
The DataSet is a memory-resident representation of data that provides a consistent relational programming model regardless of the data source. It can be used with multiple and differing data sources, with XML data, or to manage data local to the application.
The DataSet represents a complete set of data, including related tables, constraints, and relationships among the tables. The following image shows the DataSet object model. The methods and objects in a DataSet are consistent with those in the relational database model. An ADO. A DataTable is defined in the System.
Data namespace and represents a single table of memory-resident data. NET data providers. The disconnected components build the basic ADO. NET architecture. You can use these components or classes with or without data providers. For example, you can use a DataTable object with or without providers and shared or common components are the base classes for data providers.
Shared or common components are the base classes for data providers and shared by all data providers. The data provider components are specifically designed to work with different kinds of data sources. Figure represents the ADO. Answer 3: A DataSet object falls in disconnected components series. The DataSet consists of a collection of tables, rows, columns and relationships. A DataTable maps to a table in the database.
Answer 4: Connection pooling is the ability of reusing your connection to the database. This means if you enable Connection pooling in the connection object, actually you enable the re-use of the connection to more than one user. NET uses a technique called connection pooling, which minimizes the cost of repeatedly opening and closing connections.
Connection pooling reuses existing active connections with the same connection string instead of creating new connections when a request is made to the database.
It involves the use of a connection manager that is responsible for maintaining a list, or pool, of available connections for a given connection string.
Several pools exist if different connection strings ask for connection pooling. Example of Pooling: connection. The default is 0, indicating that connection will have the maximum timeout. Connection Reset: Specifies whether the connection is reset when removed from the pool. The default is true. Enlist: Specifies whether the connection is automatically enlisted in the current transaction context of the creation thread if that transaction context exists.
Load Balance Timeout: Length of time in seconds that a connection can remain idle in a connection pool before being removed. Max Pool Size: Maximum number of connections allowed in the pool. The default is Min Pool Size: Minimum number of connections maintained in the pool. The default is 0. Pooling: When true, the connection is drawn from the appropriate pool, or if necessary, created and added to the appropriate pool. A DataSet object is bound to multiple controls.
A DataSet object has slower access to data. A DataSet object is supported by Visual Studio tools. We can create relations in a dataset. A DataSet can modify data. SqlCommand carries the command in the CommandText property and this property will be used when the SqlCommand calls any of its execute methods. The queries can be in the form of Inline text, Stored Procedures or direct Table access.
An important feature of Command object is that it can be used to execute queries and Stored Procedures with Parameters. If a select query is issued, the result set it returns is usually stored in either a DataSet or a DataReader object.
For example, using this method we can retrieve a sum of sales made by a specific product, total number of records in the employee table, unique id by supplying filtering conditions and so on. Since this method performs faster we do not need to go for the Reader method just to retrieve a single scalar value. ExecuteNonQuery is useful for performing data manipulation on the database.
The return value of the ExecuteNonQuery is an integral value that represents the number of rows affected by the Operation. ExecuteReader is used when we need to retrieve rows and columns of data using the SQL select statements. We should iterate through this object to get the required values. NET provides objects that allow you to access data in various ways.
The DataSetobject allows you to store the relational model of your database. NET You can only work on connected manner. This means that when you access data, such as viewing and updating data, it is real-time, with a connection being used all the time.
This is barring, of course, you programming special routines to pull all your data into temporary tables. In connectedmodel you always get refreshed data. NET uses data in a disconnected fashion. When you access data, ADO. NET only holds the connection open long enough to either pull down the data or to make any requested updates. This makes ADO. NET efficient to use for Web applications. It's also decent for desktop applications.
You can work on connected and disconnected manner. Outlook is an example of disconnected model. We work on offline object model and when connection is required it is connected.
Connected object can be used on disconnected object. This is nice when you are working with other business applications and also helps when you are working with firewalls because data is passed as HTML and XML. ADO allows you to create client-side cursors only.
NET gives you the choice of either using client-side or server-side cursors. In ADO. NET, classes actually handle the work of cursors. The developer has the freedom of choice in internet development, for creating efficient applications.
See for more detail: What is ADO. Answer 8: A Data Adapter represents a set of data commands and a database connection to fill the dataset and update a SQL Server database. A Data Adapter contains a set of data commands and a database connection to fill the dataset and update a SQL Server database. Data Adapters form the bridge between a data source and a dataset. Data Adapters are designed depending on the specific data source. The following table shows the Data Adapter classes with their data source.
The Fill method leaves the connection in the same state as it encountered before populating the data. Update : The Update method commits the changes back to the database. Answer It is used in a disconnected architecture. Provides lower performance.
A DataSet object supports multiple tables from various databases. A Dataset supports integration with XML. A DataSet communicates with the Data Adapter only. Data Namespace Class?
Answer: The three general namespaces are System. Data, System. Common and System. Some of the provider-specific namespaces are System. OleDb, Microsoft. Odbc and System. The System. Data namespace defines classes that you can use with all the data providers or without data providers at all. This namespace also defines interfaces that are base classes for the data provider classes. The following figure shows the System. Data namespace class hierarchy.
See for more detail: ADO. Answer DataTable represents a single table in a database. In this show row and column. DataSet is a collection of data tables. In this store data record. DataTable representation in.
Fill dt ; grid. Answer DataReader holds only one table at a time. It only provides read only access mode and cannot write data. It is not required local storage to data store. Holds one row at a time. Uses less memory. DataReader do not maintain relation. DataReader representation in. ExecuteReader ; grid. Read Reads next record in the data reader. NextResult Advances the data reader to the next result during batch transactions.
Getxxx There are dozens of Getxxx methods. These methods read a specific data type value from a column. For example. GetChar will return a column value as a character and GetString as a string. Answer : CommandBuilder helps you to generate update, delete, and insert commands on a single database table for a data adapter.
Similar to other objects, each data provider has a command builder class. You pass a DataAdapter as an argument of the CommandBuilder constructor. You need to define a data provider and a data source when you create a connection. With these two, you can also specify the user ID and password depending on the type of data source. Figure shows the relationship between a connection, a data source, and a data adapter. Figure: The relationship between connection, data Adapter, and a data source.
Connection can also be connected to a Command object to execute SQL queries, which can be used to retrieve, add, update and delete data to a data source.
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