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Showing posts from August, 2015

Microsoft SQL Server_Buffer management,RAM ,checksum ,Buffer Manager, buffer cache,memory

SQL Server buffers pages in RAM to minimize disc I/O. Any 8 KB page can be buffered in-memory, and the set of all pages currently buffered is called the buffer cache. The amount of memory available to SQL Server decides how many pages will be cached in memory. The buffer cache is managed by the Buffer Manager. Either reading from or writing to any page copies it to the buffer cache. Subsequent reads or writes are redirected to the in-memory copy, rather than the on-disc version. The page is updated on the disc by the Buffer Manager only if the in-memory cache has not been referenced for some time. While writing pages back to disc, asynchronous I/O is used whereby the I/O operation is done in a background thread so that other operations do not have to wait for the I/O operation to complete. Each page is written along with its checksum when it is written. When reading the page back, its checksum is computed again and matched with the stored version to ensure the page has not been damag

Linux_Video input infrastructure,kernel-userspace,APIs , DVB API,userspace

Linux currently has two modern kernel-userspace APIs for handing video input devices: V4L2 API for video streams and radio, and DVB API for digital TV reception. Due to the complexity and diversity of different devices, and due to the large amount of formats and standards handled by those APIs, this infrastructure needs to evolve to better fit other devices. Also, a good userspace device library is the key of the success for having userspace applications to be able to work with all formats supported by those devices.

Microsoft SQL Server,relational database management system,Microsoft,database server,network ,workloads ,T-SQL,ANSI SQL

Microsoft SQL Server is a relational database management system developed by Microsoft. As a database server, it is a software product whose primary function is to store and retrieve data as requested by other software applications, be it those on the same computer or those running on another computer across a network (including the Internet). There are at least a dozen different editions of Microsoft SQL Server aimed at different audiences and for workloads ranging from small single-machine applications to large Internet-facing applications with many concurrent users. Its primary query languages are T-SQL and ANSI SQL.

Linux_User interface,CLI shells ,text-based user interfaces,userland,K Desktop Environment (KDE), GNOME, Cinnamon, Unity, LXDE, Pantheon and Xfce

The user interface, also known as the shell, is either a command-line interface (CLI), a graphical user interface (GUI), or through controls attached to the associated hardware, which is common for embedded systems. For desktop systems, the default mode is usually a graphical user interface, although the CLI is available through terminal emulator windows or on a separate virtual console. CLI shells are the text-based user interfaces, which use text for both input and output. The dominant shell used in Linux is the GNU Bourne-Again Shell (bash), originally developed for the GNU project. Most low-level Linux components, including various parts of the userland, use the CLI exclusively. The CLI is particularly suited for automation of repetitive or delayed tasks, and provides very simple inter-process communication. On desktop systems, the most popular user interfaces are the GUI shells, packaged together with extensive desktop environments, such as the K Desktop Environment (KDE), GNOME

Joomla_Extensions,components, modules, plugins, templates, and languages,boxes,login module,Joomla conversions

Joomla extensions extend the functionality of Joomla websites. Five types of extensions may be distinguished: components, modules, plugins, templates, and languages. Each of these extensions handles a specific function.     Components are the largest and most complex extensions. Most components have two parts: a site part and an administrator part. Every time a Joomla page loads, one component is called to render the main page body. Components produce the major portion of a page because a component is driven by a menu item.     Plugins are advanced extensions and are, in essence, event handlers. In the execution of any part of Joomla, a module or a component, an event may be triggered. When an event is triggered, plugins that are registered to handle that event execute. For example, a plugin could be used to block user-submitted articles and filter text. The line between plugins and components can sometimes be a little fuzzy. Sometimes large or advanced plugins are called components

Linux ,POSIX,Unix,computer operating system,open-source software development,automation controls, televisions and video game consoles

Linux is a Unix-like and mostly POSIX-compliant computer operating system assembled under the model of free and open-source software development and distribution. The defining component of Linux is the Linux kernel, an operating system kernel first released on 5 October 1991 by Linus Torvalds. The Free Software Foundation uses the name GNU/Linux to describe the operating system, which has led to some controversy. Linux was originally developed as a free operating system for Intel x86?based personal computers, but has since been ported to more computer hardware platforms than any other operating system.It is the leading operating system on servers and other big iron systems such as mainframe computers and supercomputers, but is used on only around 1.5% of desktop computers.Linux also runs on embedded systems, which are devices whose operating system is typically built into the firmware and is highly tailored to the system; this includes mobile phones, tablet computers, network routers

Joomla_Deployment,LAMP stack,control panels,Microsoft Web Platform Installer,PHP ,MySQL

Like many other web applications, Joomla may be run on a LAMP stack. Many web hosts have control panels for automatic installation of Joomla. On Windows, Joomla can be installed using the Microsoft Web Platform Installer, which automatically detects and installs dependencies, such as PHP or MySQL. Many web sites provide information on installing and maintaining Joomla sites.

Joomla,content management system (CMS),open-source,web content, web application framework,page caching, RSS feeds, printable versions of pages, news flashes, blogs, polls, search

Joomla is a free and open-source content management system (CMS) for publishing web content. It is built on a model view controller web application framework that can be used independently of the CMS. Joomla is written in PHP, uses object-oriented programming (OOP) techniques (since version 1.5) and software design patterns, stores data in a MySQL, MS SQL (since version 2.5), or PostgreSQL (since version 3.0) database, and includes features such as page caching, RSS feeds, printable versions of pages, news flashes, blogs, polls, search, and support for language internationalization. As of February 2014, Joomla has been downloaded over 50 million times.Over 7,700 free and commercial extensions are available from the official Joomla! Extension Directory, and more are available from other sources.It is estimated to be the second most used content management system on the Internet after WordPress.

Interface, Java, JavaScript, DHTML, Flash, Silverlight,operating system, Ajax, PHP

Through Java, JavaScript, DHTML, Flash, Silverlight and other technologies, application-specific methods such as drawing on the screen, playing audio, and access to the keyboard and mouse are all possible. Many services have worked to combine all of these into a more familiar interface that adopts the appearance of an operating system. General purpose techniques such as drag and drop are also supported by these technologies. Web developers often use client-side scripting to add functionality, especially to create an interactive experience that does not require page reloading. Recently, technologies have been developed to coordinate client-side scripting with server-side technologies such as PHP. Ajax, a web development technique using a combination of various technologies, is an example of technology which creates a more interactive experience.