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62-517: Oracle provides both graphical user interface (GUI) and command-line (CLI) tools for managing Data Guard configurations. Data Guard supports both physical standby and logical standby sites. Oracle Corporation makes Data Guard available only as a bundled feature included within its "Enterprise Edition" of the Oracle RDBMS . With appropriately set-up Data Guard operations, DBAs can facilitate failovers or switchovers to alternative hosts in

124-464: A "shared-everything" architecture. IBM Db2 for z/OS (the IBM mainframe operating-system) has provided a high-performance data-sharing option since the mid-1990s when IBM released its mainframe hardware and software-clustering infrastructure. In late 2009, IBM announced DB2 pureScale, a shared-disk clustering scheme for DB2 9.8 on AIX that mimics the parallel sysplex implementation behind Db2 data sharing on

186-450: A Fetch Archive Log ( FAL ) client monitors for gaps in the sequence of received logs. If it finds a gap, it may invoke one or more Fetch Archive Log (FAL) servers to run on the primary database to forward the missing item(s). Once the archived redo logs have arrived on the standby host, other processes - such as an ARCH (archiver process), an MRP (Managed Recovery Process), and/or an LSP (Logical Standby Process) - may set about applying

248-470: A GUI and some level of a CLI, although the GUIs usually receive more attention. GUI wrappers find a way around the command-line interface versions (CLI) of (typically) Linux and Unix-like software applications and their text-based UIs or typed command labels. While command-line or text-based applications allow users to run a program non-interactively, GUI wrappers atop them avoid the steep learning curve of

310-520: A Shared Nothing architecture RDBMS with the advent of the IBM SP and SP2 with the release of 7.x MPP editions, in which virtual shared drives (VSD) were used to create a Shared Everything implementation on a Shared Nothing architecture. Shared-everything architectures share both data on disk and data in memory between nodes in the cluster. This is in contrast to "shared-nothing" architectures that share none of them. Some commercially available databases offer

372-539: A case. The "Oracle Active Data Guard" option, an extra-cost facility, extends Oracle Data Guard functionality in Oracle 11g configurations. It allows read-only access on the Physical standby node at the same time as applying archived transactions from the primary node. Also it features Automatic Block Repair and Fast Incremental Backup on Physical Standby, LNS (log-write network-server) and ARCH (archiver) processes running on

434-410: A combination of technologies and devices to provide a platform that users can interact with, for the tasks of gathering and producing information. A series of elements conforming a visual language have evolved to represent information stored in computers. This makes it easier for people with few computer skills to work with and use computer software. The most common combination of such elements in GUIs

496-503: A computer queries data, it receives the current version — even if another computer recently modified that data. Oracle RAC refers to this functionality as Cache Fusion . Cache Fusion involves the ability of Oracle RAC to "fuse" the in-memory data cached physically separately on each computer into a single, global cache. The Oracle Grid Naming Service (GNS) handles name resolution in the cluster registry. The Trace File Analyzer (TFA) aids in collecting RAC diagnostic data. Relative to

558-434: A data block to disk and another node would read that data from the same disk), which had the inherent disadvantage of lackluster performance. Oracle 9i addressed this issue: RAC uses a dedicated network connection for communications internal to the cluster. Since all computers/instances in a RAC access the same database, the overall system must guarantee the coordination of data changes on different computers such that whenever

620-541: A database system. It can also reduce the human intervention required to switch between databases at disaster-recovery ("failover") or upgrade / maintenance ("switchover") time. Through the use of standby redo log files, Data Guard can minimize data loss. It supports heterogeneous configurations in which the primary and standby systems may have different CPU architectures, operating systems (for example, Microsoft Windows and Linux), operating-system binaries (32-bit/64-bit), or Oracle database binaries (32-bit/64-bit). If

682-505: A grid of items with rows of text extending sideways from the icon. Multi-row and multi-column layouts commonly found on the web are "shelf" and "waterfall". The former is found on image search engines , where images appear with a fixed height but variable length, and is typically implemented with the CSS property and parameter display: inline-block; . A waterfall layout found on Imgur and TweetDeck with fixed width but variable height per item

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744-506: A program was busy. Additionally, it was the first GUI to introduce something resembling Virtual Desktops . Windows 95 , accompanied by an extensive marketing campaign, was a major success in the marketplace at launch and shortly became the most popular desktop operating system. In 2007, with the iPhone and later in 2010 with the introduction of the iPad , Apple popularized the post-WIMP style of interaction for multi-touch screens, and those devices were considered to be milestones in

806-474: A retail store, airline self-ticket and check-in, information kiosks in a public space, like a train station or a museum, and monitors or control screens in an embedded industrial application which employ a real-time operating system (RTOS). Cell phones and handheld game systems also employ application specific touchscreen GUIs. Newer automobiles use GUIs in their navigation systems and multimedia centers, or navigation multimedia center combinations. A GUI uses

868-414: A short sequence of words and symbols. Custom functions may be used to facilitate access to frequent actions. Command-line interfaces are more lightweight , as they only recall information necessary for a task; for example, no preview thumbnails or graphical rendering of web pages. This allows greater efficiency and productivity once many commands are learned. But reaching this level takes some time because

930-430: A single database , thus providing clustering . In a non-RAC Oracle database, a single instance accesses a single database. The database consists of a collection of data files , control files, and redo logs located on disk . The instance comprises the collection of Oracle-related memory and background processes that run on a computer system. In an Oracle RAC environment, 2 or more instances concurrently access

992-470: A single database. This allows an application or user to connect to either computer and have access to a single coordinated set of data. The instances are connected with each other through an "Interconnect" which enables all the instances to be in sync in accessing the data. The main aim of Oracle RAC is to implement a clustered database to provide performance, scalability and resilience & high availability of data at instance level. Oracle RAC depends on

1054-428: A system or moved about to different places during redesigns. Also, icons and dialog boxes are usually harder for users to script. WIMPs extensively use modes , as the meaning of all keys and clicks on specific positions on the screen are redefined all the time. Command-line interfaces use modes only in limited forms, such as for current directory and environment variables . Most modern operating systems provide both

1116-664: Is a related technology that promises to deliver the representation benefits of 3D environments without their usability drawbacks of orientation problems and hidden objects. In 2006, Hillcrest Labs introduced the first ZUI for television. Other innovations include the menus on the PlayStation 2 , the menus on the Xbox , Sun's Project Looking Glass , Metisse , which was similar to Project Looking Glass, BumpTop , where users can manipulate documents and windows with realistic movement and physics as if they were physical documents, Croquet OS , which

1178-421: Is built for collaboration, and compositing window managers such as Enlightenment and Compiz . Augmented reality and virtual reality also make use of 3D GUI elements. 3D GUIs have appeared in science fiction literature and films , even before certain technologies were feasible or in common use. Oracle RAC In database computing , Oracle Real Application Clusters ( RAC ) — an option for

1240-417: Is especially common with applications designed for Unix-like operating systems. The latter used to be implemented first because it allowed the developers to focus exclusively on their product's functionality without bothering about interface details such as designing icons and placing buttons. Designing programs this way also allows users to run the program in a shell script . Many environments and games use

1302-655: Is represented by rotating a cube with faces representing each user's workspace, and window management is represented via a Rolodex -style flipping mechanism in Windows Vista (see Windows Flip 3D ). In both cases, the operating system transforms windows on-the-fly while continuing to update the content of those windows. The GUI is usually WIMP-based, although occasionally other metaphors surface, such as those used in Microsoft Bob , 3dwm, File System Navigator, File System Visualizer , 3D Mailbox, and GopherVR . Zooming (ZUI)

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1364-665: Is set to STANDBY (ALTER DATABASE GUARD STANDBY;), write to tables in the logical standby database that are not being maintained by SQL Apply. Unfortunately there are a number of unsupported objects (e.g. tables or sequences owned by SYS, tables that use table compression, tables that underlie a materialized view or Global temporary tables (GTTs)) and unsupported data types (i.e.: datatypes BFILE, ROWID, and UROWID, user-defined TYPEs, multimedia data types like Oracle Spatial, ORDDICOM, and Oracle Text Collections (e.g. nested tables, VARRAYs), SecureFile LOBs, OBJECT RELATIONAL XMLTypes and BINARY XML). Logical standby may not be appropriate in such

1426-440: Is the windows, icons, text fields, canvases, menus, pointer ( WIMP ) paradigm, especially in personal computers . The WIMP style of interaction uses a virtual input device to represent the position of a pointing device's interface , most often a mouse , and presents information organized in windows and represented with icons . Available commands are compiled together in menus, and actions are performed making gestures with

1488-551: Is usually implemented by specifying column-width: . Smaller app mobile devices such as personal digital assistants (PDAs) and smartphones typically use the WIMP elements with different unifying metaphors, due to constraints in space and available input devices. Applications for which WIMP is not well suited may use newer interaction techniques , collectively termed post-WIMP UIs. As of 2011, some touchscreen-based operating systems such as Apple's iOS ( iPhone ) and Android use

1550-592: The Oracle Database software produced by Oracle Corporation and introduced in 2001 with Oracle9i — provides software for clustering and high availability in Oracle database environments. Oracle Corporation includes RAC with the Enterprise Edition, provided the nodes are clustered using Oracle Clusterware . Oracle RAC allows multiple computers to run Oracle RDBMS software simultaneously while accessing

1612-681: The Xerox Star . These early systems spurred many other GUI efforts, including Lisp machines by Symbolics and other manufacturers, the Apple Lisa (which presented the concept of menu bar and window controls ) in 1983, the Apple Macintosh 128K in 1984, and the Atari ST with Digital Research 's GEM , and Commodore Amiga in 1985. Visi On was released in 1983 for the IBM PC compatible computers, but

1674-498: The cursor (or rather pointer ) control: mouse , pointing stick , touchpad , trackball , joystick , virtual keyboards , and head-up displays (translucent information devices at the eye level). There are also actions performed by programs that affect the GUI. For example, there are components like inotify or D-Bus to facilitate communication between computer programs. Ivan Sutherland developed Sketchpad in 1963, widely held as

1736-412: The infrastructure component Oracle Clusterware to coordinate multiple servers and their sharing of data storage. The FAN (Fast Application Notification) technology detects down-states. RAC administrators can use the srvctl tool to manage RAC configurations, Prior to Oracle 9, network-clustered Oracle databases used a storage device as the data-transfer medium (meaning that one node would write

1798-669: The resource mastering (or ownership-transfer) is minimal for fewer than three nodes, as the request for any resource in the cluster can be obtained in a maximum of three hops (owner-master-requestor). This makes Oracle RAC horizontally scalable with many nodes. Application vendors (such as SAP ) use Oracle RAC to demonstrate the scalability of their application. Most of the biggest OLTP benchmarks are on Oracle RAC. Oracle RAC 11g supports up to 100 nodes. For some applications, RAC may require careful application partitioning to enhance performance . An application that scales linearly on an SMP machine may scale linearly under RAC. However, if

1860-616: The 1970s, Engelbart's ideas were further refined and extended to graphics by researchers at Xerox PARC and specifically Alan Kay , who went beyond text-based hyperlinks and used a GUI as the main interface for the Smalltalk programming language , which ran on the Xerox Alto computer , released in 1973. Most modern general-purpose GUIs are derived from this system. The Xerox PARC GUI consisted of graphical elements such as windows , menus , radio buttons , and check boxes . The concept of icons

1922-506: The GUIs advantages, many reviewers questioned the value of the entire concept, citing hardware limits, and problems in finding compatible software. In 1984, Apple released a television commercial which introduced the Apple Macintosh during the telecast of Super Bowl XVIII by CBS , with allusions to George Orwell 's noted novel Nineteen Eighty-Four . The goal of the commercial was to make people think about computers, identifying

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1984-639: The Unix flavors (except for Linux and Windows where Oracle provided free clusterware called Cluster Ready Services or CRS ), as of Oracle 10g, Oracle's clusterware product was available for all operating systems. With the release of Oracle Database 10g Release 2 (10.2), Cluster Ready Services was renamed to Oracle Clusterware. When using Oracle 10g or higher, Oracle Clusterware is the only clusterware that you need for most platforms on which Oracle RAC operates (except for Tru cluster, in which case you need vendor clusterware). You can still use clusterware from other vendors, if

2046-467: The application cannot scale linearly on SMP, it will not scale when ported to RAC. In short, the application scalability is based on how well the application scales in a single instance . Shared-nothing and shared-everything architectures each have advantages over the other. DBMS vendors and industry analysts regularly debate the matter; for example, Microsoft touts a comparison of its SQL Server 2005 with Oracle 10g RAC. Oracle Corporation offered

2108-401: The class of GUIs named post-WIMP. These support styles of interaction using more than one finger in contact with a display, which allows actions such as pinching and rotating, which are unsupported by one pointer and mouse. Human interface devices , for the efficient interaction with a GUI include a computer keyboard , especially used together with keyboard shortcuts , pointing devices for

2170-482: The clusterware is certified for Oracle RAC. In RAC, the write-transaction must take ownership of the relevant area of the database: typically, this involves a request across the cluster interconnection (local IP network) to transfer the data-block ownership from another node to the one wishing to do the write. This takes a relatively long time (from a few to tens of milliseconds ) compared to single database-node using in-memory operations. For many types of applications,

2232-457: The command words may not be easily discoverable or mnemonic . Also, using the command line can become slow and error-prone when users must enter long commands comprising many parameters or several different filenames at once. However, windows, icons, menus, pointer ( WIMP ) interfaces present users with many widgets that represent and can trigger some of the system's available commands. GUIs can be made quite hard when dialogs are buried deep in

2294-413: The command-line, which requires commands to be typed on the keyboard . By starting a GUI wrapper, users can intuitively interact with, start, stop, and change its working parameters, through graphical icons and visual indicators of a desktop environment , for example. Applications may also provide both interfaces, and when they do the GUI is usually a WIMP wrapper around the command-line version. This

2356-473: The data in the database will be exactly the same as in the primary database. Physical standby databases can function either in managed-recovery mode or in read-only mode, but not in both modes at the same time (unless the databases are at Oracle Database 11.1 or higher and the Active Data Guard option is licensed - see below). The standby makes use of "Redo Apply" technology. Physical standby databases have

2418-571: The designer's work to change the interface as user needs evolve. Good GUI design relates to users more, and to system architecture less. Large widgets, such as windows , usually provide a frame or container for the main presentation content such as a web page, email message, or drawing. Smaller ones usually act as a user-input tool. A GUI may be designed for the requirements of a vertical market as application-specific GUIs. Examples include automated teller machines (ATM), point of sale (POS) touchscreens at restaurants, self-service checkouts used in

2480-485: The development of mobile devices . The GUIs familiar to most people as of the mid-late 2010s are Microsoft Windows , macOS , and the X Window System interfaces for desktop and laptop computers, and Android , Apple's iOS , Symbian , BlackBerry OS , Windows Phone / Windows 10 Mobile , Tizen , WebOS , and Firefox OS for handheld ( smartphone ) devices. Since the commands available in command line interfaces can be many, complex operations can be performed using

2542-435: The display represents a desktop, on which documents and folders of documents can be placed. Window managers and other software combine to simulate the desktop environment with varying degrees of realism. Entries may appear in a list to make space for text and details, or in a grid for compactness and larger icons with little space underneath for text. Variations in between exist, such as a list with multiple columns of items and

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2604-593: The first graphical computer-aided design program. It used a light pen to create and manipulate objects in engineering drawings in realtime with coordinated graphics. In the late 1960s, researchers at the Stanford Research Institute , led by Douglas Engelbart , developed the On-Line System (NLS), which used text-based hyperlinks manipulated with a then-new device: the mouse . (A 1968 demonstration of NLS became known as " The Mother of All Demos ".) In

2666-485: The interface found in current versions of Microsoft Windows, and in various desktop environments for Unix-like operating systems , such as macOS and Linux . Thus most current GUIs have largely common idioms. GUIs were a hot topic in the early 1980s. The Apple Lisa was released in 1983, and various windowing systems existed for DOS operating systems (including PC GEM and PC/GEOS ). Individual applications for many platforms presented their own GUI variants. Despite

2728-413: The kind of data they hold. The widgets of a well-designed interface are selected to support the actions necessary to achieve the goals of users. A model–view–controller allows flexible structures in which the interface is independent of and indirectly linked to application functions, so the GUI can be customized easily. This allows users to select or design a different skin or theme at will, and eases

2790-414: The log contents to the standby database. The use of standby redo logs can speed up the application of changes to a standby database with real-time apply. The Data Guard Connection process ( DRCX ) plays a role in transferring data between databases. The Data Guard Broker subsystem can aid in the setup, management and monitoring of Data Guard configurations. Data Guard provides high availability for

2852-621: The mainframe. In February 2008, Sybase released its Adaptive Server Enterprise , Cluster Edition. It resembles Oracle RAC in its shared-everything design. Although technically not shared-everything, Sybase also provides a column-based relational database focused on analytic and datawarehouse applications called Sybase IQ that can be configured to run in a shared disk mode. Cloud Native Databases, such as Amazon Aurora and POLARDB of Alibaba Cloud , are implemented with "shared-everything" architecture on top of cloud-based distributed file system. Shared-nothing architectures share neither

2914-435: The methods of 3D graphics to project 3D GUI objects onto the screen. The use of 3D graphics has become increasingly common in mainstream operating systems (ex. Windows Aero , and Aqua (MacOS)) to create attractive interfaces, termed eye candy (which includes, for example, the use of drop shadows underneath windows and the cursor ), or for functional purposes only possible using three dimensions. For example, user switching

2976-418: The network link connecting primary and standby is over-subscribed, the redo logs are not shipped in chronological order, which can result in large gaps appearing in the available redo at the standby. Such a condition results in the standby being behind the primary. This can be overcome, using Oracle’ Active Data Guard Farsync technology. The same release of Oracle Database Enterprise Edition must be installed on

3038-680: The perceived steep learning curve of command-line interfaces (CLIs), which require commands to be typed on a computer keyboard . The actions in a GUI are usually performed through direct manipulation of the graphical elements. Beyond computers, GUIs are used in many handheld mobile devices such as MP3 players, portable media players, gaming devices, smartphones and smaller household, office and industrial controls . The term GUI tends not to be applied to other lower- display resolution types of interfaces , such as video games (where head-up displays ( HUDs ) are preferred), or not including flat screens like volumetric displays because

3100-403: The pointing device. A window manager facilitates the interactions between windows, applications , and the windowing system . The windowing system handles hardware devices such as pointing devices, graphics hardware, and positioning of the pointer. In personal computers , all these elements are modeled through a desktop metaphor to produce a simulation called a desktop environment in which

3162-671: The primary database and all standby databases, except during rolling database upgrades using logical standby databases. Oracle Data Guard is available only as a feature of Oracle Database Enterprise Edition. Oracle RAC Graphical user interface A graphical user interface , or GUI ( / ˈ ɡ uː i / GOO -ee ), is a form of user interface that allows users to interact with electronic devices through graphical icons and visual indicators such as secondary notation . In many applications, GUIs are used instead of text-based UIs , which are based on typed command labels or text navigation. GUIs were introduced in reaction to

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3224-458: The primary database select archived redo logs and send them to the standby-database host, where the RFS (remote file server) background process within the Oracle instance performs the task of receiving archived redo logs originating from the primary database and writing them to a standby redo log (SRL). Alternatively, a supplementary mechanism may transfer the archived redo logs. On the standby database

3286-453: The same DBID identifiers as their primary equivalents. Logical standby databases convert the redo generated at the primary database into data and SQL and then re-apply those SQL transactions on the logical standby. Thus, physical structures and organization will be different from the primary database. Users can read from logical standby databases while the changes are being applied and, if the GUARD

3348-459: The same or alternative locations. For the purposes of Data Guard, each Oracle database functions either in a primary database role or in a standby database role - with the ability to transition from one role to the other. A physical standby database replicates the exact contents of its primary database across the Oracle Net network layer . While the relative physical storage locations can differ,

3410-595: The single-instance Oracle database, Oracle RAC adds additional complexity. While database automation makes sense for single-instance databases, it becomes even more necessary for clustered databases because of their increased complexity. Oracle Real Application Clusters (RAC), introduced with Oracle 9i in 2001, supersedes the Oracle Parallel Server (OPS) database option. Whereas Oracle9i required an external clusterware (known as vendor clusterware like TruCluster Veritas Cluster Server or Sun Cluster ) for most of

3472-509: The system never reached commercial production. The first commercially available computer with a GUI was the 1979 PERQ workstation , manufactured by Three Rivers Computer Corporation. Its design was heavily influenced by the work at Xerox PARC. In 1981, Xerox eventually commercialized the ideas from the Alto in the form of a new and enhanced system – the Xerox 8010 Information System – more commonly known as

3534-492: The term is restricted to the scope of 2D display screens able to describe generic information, in the tradition of the computer science research at the Xerox Palo Alto Research Center . Designing the visual composition and temporal behavior of a GUI is an important part of software application programming in the area of human–computer interaction . Its goal is to enhance the efficiency and ease of use for

3596-461: The time spent coordinating block access across systems is low relative to the many operations on the system, and RAC will scale comparably to a single system. Moreover, high read-transactional databases (such as data-warehousing applications) work very well under RAC, as no need for ownership-transfer exists. (Oracle 11g has made many enhancements in this area and performs a lot better than earlier versions for read-only workloads. ) The overhead on

3658-456: The underlying logical design of a stored program , a design discipline named usability . Methods of user-centered design are used to ensure that the visual language introduced in the design is well-tailored to the tasks. The visible graphical interface features of an application are sometimes referred to as chrome or GUI . Typically, users interact with information by manipulating visual widgets that allow for interactions appropriate to

3720-466: The user-friendly interface as a personal computer which departed from prior business-oriented systems, and becoming a signature representation of Apple products. In 1985, Commodore released the Amiga 1000 , along with Workbench and Kickstart 1.0 (which contained Intuition ). This interface ran as a separate task, meaning it was very responsive and, unlike other GUIs of the time, it didn't freeze up when

3782-399: Was later introduced by David Canfield Smith , who had written a thesis on the subject under the guidance of Kay. The PARC GUI employs a pointing device along with a keyboard. These aspects can be emphasized by using the alternative term and acronym for windows, icons, menus, pointing device ( WIMP ). This effort culminated in the 1973 Xerox Alto , the first computer with a GUI, though

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3844-574: Was never popular due to its high hardware demands. Nevertheless, it was a crucial influence on the contemporary development of Microsoft Windows . Apple, Digital Research, IBM and Microsoft used many of Xerox's ideas to develop products, and IBM's Common User Access specifications formed the basis of the GUIs used in Microsoft Windows, IBM OS/2 Presentation Manager , and the Unix Motif toolkit and window manager . These ideas evolved to create

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