Take a look at the ExecuteReader method instead if you only want to read once from your returned result-set. The SqlDataAdapter object takes much more server memory, especially as the resultset size increases, and you need to wait until your data is loaded into server memory before you can use the SqlDataAdapter object. However, once you have the SqlDataAdapter loaded, you are not limited to a single read-through of the data… you can look through the returned DataSet as often as you like and can further apply filters, including applying Linq filters.
Also a nice feature is that you can return the results of multiple queries that you can use to populate one or more DataTables with. Encapsulating multiple result sets in a single call to your database is especially useful if you want to minimize the back and forth communication between your Web server and your database server. The example code below shows how to run a stored procedure that returns the results of three separate select statements, and then how to populate the DataTable objects with the results of two of the queries, and to populate a GridView control with the results of the third result.
I specialize in Web application development with a focus on building secure systems, integrating applications, and designing robust database structures. View all posts by Justin Cooney. You are commenting using your WordPress. You are commenting using your Google account. You are commenting using your Twitter account. You are commenting using your Facebook account.
Notify me of new comments via email. Notify me of new posts via email. Skip to content Justin Cooney. ConnectionStrings "TestDbConn". StoredProcedure conn. Net ADO. Net is a model, a part of the. Net framework that is used by the. Net applications for retrieving, accessing and updating data. Net object model is nothing but the structured process flow through various components. The data residing in a data store or database is retrieved through the data provider.
Various components of the data provider retrieve data for the application and update data. A data provider is used for connecting to a database, executing commands and retrieving data, storing it in a dataset, reading the retrieved data and updating the database. A command is a SQL statement or a stored procedure used to retrieve, insert, delete or modify data in a data source. This is integral to the working of ADO. Net since data is transferred to and from a database through a data adapter.
It retrieves data from a database into a dataset and updates the database. When changes are made to the dataset, the changes in the database are actually done by the data adapter. DataSet is an in-memory representation of data. It is a disconnected, cached set of records that are retrieved from a database. When a connection is established with the database, the data adapter creates a dataset and stores data in it. After the data is retrieved and stored in a dataset, the connection with the database is closed.
This is called the 'disconnected architecture'. Using SQL statements you can create database objects programmatically such as a table, view, stored procedure, rule, index and so on.
It also provides commands to alter a database and database schemas for example adding and deleting a column from a database table, adding some constraints to a column and so on. This example shows you how to create a new database table, add data to it, create a view of the data, alter database table and then delete the newly created table.
In this application, I'll create a SQL Server database, create a database table, add data to it, create database objects such as views, stored procedures, rules, and index and view data in the data grid using Sql data provider. To test this application, create a Widows application add a data grid control and some button controls. You can even test code by adding only one button or one button for each activity. Our application form looks like Figure 1.
Figure 1. Creating a database and it's object application. After adding controls, add the following variables in the beginning of the form class. Button Private button1 As System. Open Then conn. Show ae. Listing 1. Depending on the database type, you can also set values of database size, growth and file name.
Listing 2. Creating a SQL Server database. Now next step is to create a table. In this statement you define the table and schema table columns and their data types.
Listing 3 creates a table myTable with four column listed in Table 1. EventArgs ' Open the connection If conn. Listing 5. Creating a stored procedure programmatically.
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