Oracle Database

7 Key excerpts on "Oracle Database"

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  Database Objects, Statements, Languages & SQL

  • (Author)
  • 2014(Publication Date)
  • White Word Publications

    (Publisher)

  ________________________ WORLD TECHNOLOGIES ________________________ Chapter 9 Oracle Database The Oracle Database (commonly referred to as Oracle RDBMS or simply as Oracle ) is an object-relational database management system (ORDBMS) produced and marketed by Oracle Corporation. Larry Ellison and his friends and former co-workers Bob Miner and Ed Oates started the consultancy Software Development Laboratories (SDL) in 1977. SDL developed the original version of the Oracle software. The name Oracle comes from the code-name of a CIA-funded project Ellison had worked on while previously employed by Ampex. Physical and logical structures An Oracle Database system—identified by an alphanumeric system identifier or SID— comprises at least one instance of the application, along with data storage. An instance identified persistently by an instantiation number (or activation id: SYS.V_$DATABASE.ACTIVATION#)—comprises a set of operating-system processes and memory-structures that interact with the storage. Typical processes include PMON (the process monitor) and SMON (the system monitor). Users of the Oracle Databases refer to the server-side memory-structure as the SGA (System Global Area). The SGA typically holds cache information such as data-buffers, SQL commands, and user information. In addition to storage, the database consists of online redo logs (or logs), which hold transactional history. Processes can in turn archive the online redo logs into archive logs (offline redo logs), which provide the basis (if necessary) for data recovery and for some forms of data replication. If the Oracle Database administrator has implemented Oracle RAC (Real Application Clusters), then multiple instances, usually on different servers, attach to a central storage array. This scenario offers advantages such as better performance, scalability and redundancy. However, support becomes more complex, and many sites do not use RAC.

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  OCA: Oracle Database 12c Administrator Certified Associate Study Guide

  Exams 1Z0-061 and 1Z0-062

  • Biju Thomas(Author)
  • 2014(Publication Date)
  • Sybex

    (Publisher)

  Chapter 1

  Introducing Oracle Database 12c RDBMS

  Oracle Database 12c: SQL Fundamentals exam objectives covered in this chapter:

  • Introduction
    • Describe the features of Oracle Database 12c .
    • Describe the salient features of Oracle Cloud 12c .
    • Describe Oracle server’s implementation of RDBMS and object relational database management system (ORDBMS).

  Organizations and individuals collect and use a variety of information (data). A database collects data, stores and organizes data, and retrieves related data used by a business. Oracle is the world’s most widely used database management system. With the release of its Database 12c , Oracle has enhanced the capabilities of its feature-rich database to include cloud architecture. The c in 12c stands for cloud computing. From Oracle version 8 onward, Oracle includes the core emphasis of the release along with the version number in its name. Versions 8 and 9 are called i to indicate Internet computing; versions 10 and 11 are called g for grid computing.

  With the cloud enablement, Oracle Database 12c lets you manage many databases as one, thereby reducing overhead and valuable resource consumption.

  This chapter will introduce you to the Oracle Database 12c high-level components and how the Oracle Database is organized. You will also learn about the relational and object capabilities of the database, and the tools available for database administrators (DBAs) to retrieve information and manage the database.

  Exam objectives are subject to change at any time without prior notice and at Oracle’s sole discretion. Please visit Oracle’s Training and Certification website at http://www.oracle.com/education/certification for the most current exam objectives.

  Relational Database Management Systems

  A database management system (DBMS) controls the storage, organization, and retrieval of data. In a DBMS, the kernel code is the software piece that manages the storage and memory component of the database. There is metadata in the DBMS that keeps track of all the components of the database, also known as the dictionary. The code or language used to retrieve data from the database is known as SQL, which stands for Structured Query Language

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  Oracle Database Performance and Scalability

  A Quantitative Approach

  • Henry H. Liu(Author)
  • 2011(Publication Date)
  • Wiley-IEEE Computer Society Pr

    (Publisher)

  An Oracle Server consists of an Oracle instance and an Oracle Database. An Oracle Database is a logical entity from the data perspective. For example, the constituents of a database include schemas, tables, indexes, views, triggers, stored procedures, dictionaries, as well as users, and so on. Nevertheless, an Oracle instance is more of a physical entity from the system resource perspective with such constituents as processes that perform various tasks, memory areas that hold various types of data, and data files residing on physical disks, etc. An instance can operate on one database only, whereas a database can be operated upon by more than one instance in a clustered environment for high-availability. We will elaborate more on the concepts of database and instance later when we discuss Oracle architecture. To help you get to know about Oracle quickly, in the next few chapters, I'll walk you through on how to set up and get around an Oracle Database server using the latest version of Oracle 11g. Then I'll guide you through a tour of an Oracle Server to help you learn various basic concepts and building blocks of an Oracle Server. There is no better way in learning a software product than actually getting your hands dirty and experimenting with the product with the guidance of the well-written product documents or a more pertinent text such as this book. 1.4 Summary This chapter briefly introduced some basic concepts such as standard versus flavored SQLs, relational versus object-oriented databases, and an instance versus a database in Oracle's context. The purpose is to help you see the forests before seeing the trees to which the remainder of this book will be devoted

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  Oracle SQL

  Jumpstart with Examples

  • Gavin JT Powell, Carol McCullough-Dieter(Authors)
  • 2004(Publication Date)
  • Digital Press

    (Publisher)

  In other words, the people invented the different databases, not the compa-nies, where people moved between different companies. Additionally, numerous object databases have been developed. Object databases generally Figure 1.6 Including Multimedia in a Relational Database. 6 1.1 A Little History have distinct applications. Some object databases have their roots in rela-tional technology, once again in terms of the movement of personnel skills. 1.1.3 The Evolution of Oracle Database In the evolution of Oracle Corporation software, certain milestones were significant: 1979 . RSI released the first version of Oracle using a version of SQL. RSI is the original name of Oracle Corporation. Early 1980s . RSI was renamed Oracle Corporation, plus cross-plat-form capabilities and portable toolsets were introduced. Mid-1980s . Client-server environments and 4GL were introduced. 4GL is an acronym for a fourth-generation programming language. Late 1980s . Oracle6 was released. The first application Oracle Finan-cials was introduced, and PL/SQL or Programming Language for SQL Figure 1.7 The Origins of Databases. 1.1 A Little History 7 Chapter 1 was included. PL/SQL allows execution of SQL commands in blocks, where sequentially executed lines of code can depend on previously executed lines of code, much like a programming language. SQL is not a programming language, however. SQL is a coded tool or shorthand method of accessing groups of rows from a relational database. Early 1990s . Oracle7 was released. Oracle7 included Referential Integrity, cost-based statistics for optimization, and clustering. Ref-erential Integrity is important for automated maintenance of accu-racy of related data sets. Cost-based optimization uses statistics, providing a realistic picture rather than one based on “intelligent” rules. Rule-based optimization is a best guess for query performance optimization. Cost-based optimization is vastly superior to rule-based optimization.

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  The CIO's Guide to Oracle Products and Solutions

  • Jessica Keyes(Author)
  • 2014(Publication Date)
  • Auerbach Publications

    (Publisher)

  A database is an organization method that links files together as required. In nonrelational systems (e.g., hierarchical, network, etc.), records in one file contain embedded pointers to the locations of records in another, such as customers to orders and vendors to purchases. These are fixed links set up ahead of time to speed up daily processing. An RDBMS is software designed to manage a collection of data, where data is organized into related sets of tables, rows, and columns so that relation-ships between and among data can be established. For example, a vehicle database can contain two tables, one for customer information and one for vehicle information. An “owns” relationship is then established between the two tables. A multidimensional database management system (MDDBMS) is specifically designed for efficient storage and retrieval of large volumes of data. Multidimensional databases are organized into fact tables and dimensions that intersect with the facts table to identify what the fact per-tains to. Databases of this construction are used for online analytical pro-cessing, also known as OLAP. Data Warehouse: Data Marts A data warehouse is a database designed to support decision making in an organization or enterprise. It is refreshed, or batch updated, and can contain massive amounts of data. When the database is organized for one department or function, it is often called a data mart rather than a data warehouse, as shown in Figure 6.2. The data in a data warehouse is typically historical and static in nature. Data marts also contain numerous summary levels. They are structured to support a variety of elaborate analytical queries on large amounts of data that can require extensive searching. 180 • The CIO's Guide to Oracle Products and Solutions A data warehouse is a record of an enterprise’s past transactional and operational information, stored in a database designed for efficient data analysis and reporting (especially OLAP).

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  Wiley Pathways Introduction to Database Management

  • Mark L. Gillenson, Paulraj Ponniah, Alex Kriegel, Boris M. Trukhnov, Allen G. Taylor, Gavin Powell, Frank Miller(Authors)
  • 2012(Publication Date)
  • Wiley

    (Publisher)

  Keep in mind throughout this chapter that databases and DBMSs have different roles and different components. The database, while a complicated entity in itself, at its core is simply where we store the data. The DBMS contains all of the other components that make the database a viable storage and retrieval tool. 2.1 Introduction to Key Database Concepts Today, almost all organizations depend on their database systems for the crucial information they need to run their business. In every industry, from the small mom and pop business to multinational enterprises and government agencies, database systems are the norm for information storage and retrieval. Commerce, whether traditional brick and mortar or Internet-based e-commerce, thrive or die based on how they use the data they collect. Database and Web technologies have merged into something significantly more powerful than either one alone. The Information Technology (IT) department of today’s organization has the primary responsibility for designing, supporting, and maintaining database sys- tems. However, IT personnel aren’t the only ones who need at least some under- standing of database technologies and what they can do for a business. Data, in today’s rapidly changing environment, is everybody’s business. 2.1.1 Database Approach to Data As you learned in Chapter 1, a database can be defined as an ordered collection of related data elements intended to meet the information needs of an organi- zation and designed to be shared by multiple users, as described in Figure 2-1. Let’s break the characteristics of a database down: ▲ A database is an ordered collection. It is a collection of data elements— not a random group, but a collection put together deliberately, with proper order. The data elements are linked together in the most logical manner. 26 INTRODUCING DATABASES AND DATABASE MANAGEMENT SYSTEMS ▲ A database contains related data elements.

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  Introduction to Database and Knowledge-Base Systems

  • S Krishna(Author)
  • 1992(Publication Date)
  • WSPC

    (Publisher)

  Chapter 12 Object-Oriented Database Systems 12.1 Introduction Database management systems have been eminently successful in providing data management services for a variety of organizations with diverse applications. With rapid and continuous advance in computer tech-nology, however, new applications become feasible. The traditional ap-plications targeted by database management systems are those of business information systems. The word business here is a general term encom-passing activities of government, public and private enterprises, academic institutions, hospitals and other organizations. The information in these sys-tems can be effectively organized as tables with columns containing values from simple and atomic domains like integers, character strings, and real numbers. The more recent applications, however, do not fit well into this simple and inflexible mold. Some of these appdcations are: 1. Design databases: Design databases are required to assist in the designing of complex systems. Complex electronic, mechanical and struc-tural engineering systems and software systems must be described in ex-haustive detail before they can be built or manufactured. These descriptions wdl be organized at several levels of detail and in terms of different design representations. For electronic systems for example, the descriptions might range from board level to transistor level, and in terms of devices to those 302 Object-Oriented Database Systems of functional representations. Representation of composition relationships or assembly-part relationships is required. Further, design systems need the concepts of versions and equivalence of units across different repre-sentations. Both of these need the definition of an identity separate from aspects of current version or representation.

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