An Index is a copy of database table that has been reduced to certain fields and the copy is always in sorted form. The index also contains a pointer to the corresponding record of the actual table so that the fields not contained in the index can also be read. Index contains a value and […]
DEFINITION OF DATA MODEL Is the process of structuring and organizing data. TYPES OF DATA MODELS (1) Flat (2) Hierarchical (3) Network (4) Relational (5) Object-Relational and (6)Star Schema SIGNIFICANCE OF DATA MODEL (1) A well-developed data model can foster improved understanding of the organization (2) Data model helps in structuring and organizing
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Crash recovery is the process by which the database is moved back to a consistent and usable state. This is done by rolling back incomplete transactions and completing committed transactions that were still in memory when the crash occurred. When the database is in a consistent and usable state, it has attained what is known
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Computer virus is a software program written with malicious intentions. They are intentionally written by some software developer to cause severe damage for the computer, programs, and data files in which it found itself. A computer virus has the ability to replicates itself by changing other programs to include a copy of itself. Examples of
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The Origins of the internet dates back to1960s when the United State funded research projects of its military agencies to build robust, fault-tolerant and distributed computer network. The internet is a global system of interconnected computer network that use the standard internet protocol suite (TCP/IP) to serve billions of users worldwide. It is a network
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There are various ways in which viruses can attack computer system; When you download or open attachment in e-mail message or by instant messaging messages Installing unknown program from unreliable and suspicious looking web sites Illegal duplication of software from one computer to another e.g. computer games etc. When you use infected flask h drive
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The following are some of the prominent computer professional bodies in Nigeria. Nigeria Computer Society (NCS) Institute Of Management Information System. (IMIS) Computer Professional Registration Council of Nigeria (CPN) Information Technology Association of Nigeria (CPN) Nigeria Internet Group (NIG) Nigeria Computer Society (NCS) The Nigeria Computer Society (NCS) formed in 1978 as Computer Association of
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DEFINITION OF DATA SECURITY Data security is the practice of keeping data protected from corruption and unauthorized access. The focus behind data security is to ensure privacy while protecting personal or corporate data. It is a means of putting in place the different form of information security controls to protect database against compromise of
Computer personnel are those who assemble, install, repair and operate the computer system. The term equally includes those people who make their living out of the computer industry. They include the following: Database Administrator Software programmer Hardware Engineers System analysts Web developers Computer support specialist Network Administrator Network Engineers Computer Technician Microsoft office specialist Computer
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A Distributed database (DDB) is a collection of multiple, logical interrelated database distributed over a computer network. A Distributed database management system (DDBMS) is the software that manages the DDB and provides an access mechanism that makes this distribution transparent to the users. A distributed database system is a system that permits physical data storage
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Maintenance is highly essential in order to prolong its contributing functionality. SOFTWARE MAINTENANCE The maintenance of programs inside the computer system such as virus, a spyware removal, back up software and a registry removal, cleaner. Every PC should be installed with an anti virus, a spyware removal application back up and a registry cleanser. Some
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Maintenance of computer hardware is a way of taking care, repairing and replacing broken and failing computer hardware. Maintenance is necessary on computer to avoid hardware failure or loosing valuable information and most times, hardware breaks without notice. Excess heat accelerates the deterioration of the delicate circuits in the system. Dust and dirt are the
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DENSE INDEX This is said to be dense if it contains (at least) one data entry for every search key value that appears in a record in the indexed file. In a dense index, index record appears for every search key value in the file or table. That is every search key in the index
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A computer network is a system that connects two or more computers together using a communication link. It describes a processing system with a number of independent, relatively low-speed, online, simultaneously usable workstations. In a network, remotely located computer stations are connected to a centrally located sophisticated, high-speed processor via a communication link (telephone lines,
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Crash recovery is the process by which the database is moved back to a consistent and usable state. This is done by rolling back incomplete transactions and completing committed transactions that were still in memory when the crash occurred. When the database is in a consistent and usable state, it has attained what is known
Parallel Database improve processing and input/output speeds by using multiple CPU and disks in parallel. A Parallel Database system seeks to improve performance through parallelization of various operations, such as loading data, building indexes and evaluating queries. In Parallel processing, many operations are performed simultaneously, as opposed to serial processing, in which the computational steps