Article Desktop

The OleDbDataReader (and SQLDataReader) runs a query and provides once-only access to the results. The DataReader is appropriate for once-off recovery and display of data.

The OleDbDataAdapter (and SqlDataAdapter) runs a query and stores the results in a DataTable.

This is used when the results need to be counted, paged, sorted and so on.

A DataSet contains one or more DataTables

A DataTable stores data in a database-type row-and column format. It is an in-memory object which stores the information in rows and columns. The DataTable uses the DataAdapter’s ‘fill’ method to run the query and retrieve the data (and the field name and data type). The DataTable is a copy in memory to the data in the database and it does not remain connected to the database whilst it is scrolled or paged or sorted.

A DataRelation defines a logical relationship between two DataTables

A DataView provides a sorted or filtered view of the contents of a DataTable

The objects used to make connections, provide a connection string, open a connection and so on are contained in the Namespaces “System.Data” and “System.Data.OleDb” or (for SQL Server) “System.Data.SqlClient”

Most of the rest of the example code (and the DataGrid) is the same. These are the differences:-

Dim dap As OleDbDataAdapter
Dim dst As DataSet

The dataset is defined and then filled. This is the datasource for the Grid, which is then bound.

dst = New DataSet()
dap.Fill(dst,”text”)
grid.DataSource = dst.Tables(”text”)
grid.DataBind

Use DataReader when you need just to display the data in one go - which is not all that common.

Common errors that occurred at starting time, run time. Most Beginners users have a difficulties with common errors. So some of them are listed below. Those are covered from Programing Language like C, C++, PHP, ASP, ASP.net etc.

1.Providing Spaces between the operators like = =,< =,> = and ! =.

2.Use operators = instead of ==.

3.Take identifier as KeyWord.

4.Starting and Ending brace doesnot match correctly.

5.Uninitialised Variables.

6.Placing commas instead of semicolons.

7.Placing semicolon immediately after for OR while condition.

8.Placing a semicolon immediately after a function header.

9.Define function inside another function.

10.Filename is not correct while reference from another file OR Including (In both Case and Spell)

11.Expected Error Like , ;

12.Use the function that is given in Higher Version Or in other Library.

13.Infinite loop condition.

14.Use of function without declaration. A typical error in C++.

15.Variable Declaration error like variable that use in whole coding should be declare as Global Variable.

16.Object Reference cannot be set as an instance of object. Very common Error in Dot Net. This can be solved by declaring object as
bq. Dim ds as dataset
bq. ds = New Dataset(”temp”)

17.Use same object twice for different purpose. Like in asp/asp.net Recordset rs.

Here is the first web broswer history i found on internet!

Tim Berners-Lee, who invented the World Wide Web in 1989 and first deployed a working system in 1990, did so by writing a web browser for the NeXTStep operating system. The original “WorldWideWeb” browser program had a graphical user interface and so on and is definitely recognizable to most people as a web browser. However, WorldWideWeb did not support graphics embedded in pages when it was first released. You can learn more about the original “WorldWideWeb” browser from Tim Berners-Lee himself.

Since WorldWideWeb had a graphical user interface (GUI), it could be called a graphical web browser. However it did not display graphics as part of web pages. That did not happen until the arrival of NCSA Mosaic 2.0.

The first graphical web browser to become truly popular and capture the imagination of the public was NCSA Mosaic. Developed by Marc Andreessen, Jamie Zawinski and others who later went on to create the Netscape browser, NCSA Mosaic was the first to be available for Microsoft Windows, the Macintosh, and the Unix X Window System, which made it possible to bring the web to the average user. The first version appeared in March 1993. The “inline images,” such as the boutell.com logo at the top of this page, that are an integral part of almost every web page today were introduced by NCSA Mosaic 2.0, in January of 1994. Mosaic 2.0 also introduced forms.

Netscape is the browser that introduced most all of the remaining major features that define a web browser as we know it. The first version of Netscape appeared in October 1994 under the code name “Mozilla.” Netscape 1.0’s early beta versions introduced the “progressive rendering” of pages and images, meaning that the page begins to appear and the text can be read even before all of the text and/or images have been completely downloaded. Version 1.1, in March 1995, introduced HTML tables, which are now used in the vast majority of web pages to provide page layout. Version 2.0, in October 1995, introduced frames, Java applets, and JavaScript. Version 2.0 was the last version of Netscape to introduce a major feature of the web as we know it today; later versions improved reliability and stability and introduced features that did not catch on as standards for all browsers. In 1998, Netscape decided to release their browser source code as open source software, and the Mozilla project began.

Microsoft Internet Explorer is by far the most common web browser in use as of this writing. Internet Explorer 1.0, released in August 1995, broke no important new ground in a way that became part of a future standard. Later versions of Internet Explorer quickly caught up; Internet Explorer 3.0 was very close to Netscape 2.0’s feature set. In July 1996, Internet Explorer 3.0 beta introduced the first useful implementation of cascading style sheets, which allow better control of the exact appearance of web pages. In April 1997, Internet Explorer 4.0 introduced the first quality implementation of the Document Object Model (DOM), which allows Javascript to modify the appearance and content of a web page after it has been loaded.

Which is next

Lot’s of times many files in your PC are undeletable. Well, here is a tip to delete anything You want!

Open a Command Prompt window and leave it open. Close all open programs

Click Start, Run and enter TASKMGR.EXE

Go to the Processes tab and End Process on Explorer.exe. Leave Task Manager open

Go back to the Command Prompt window and change to the directory the AVI (or other undeletable file) is located in

At the command prompt type DEL where is the file you wish to delete

Go back to Task Manager, click File, New Task and enter EXPLORER.EXE to restart the GUI shell

Close Task Manager

Ok, No problem again with these awful undeletable files.