Necessary Definition of Database


  1. Database Management System :  Interrelated data and a sets of program by which we can access and manipulate those data is called Data Management System.
  2. Data: Data is sequence of digit. data is those elements which will be information after processed.
there are three type of data
such as i)      Numeric
            ii)         Textual
iii)                 Graphical
  1. Information : information is processed data.
  2. Data structure : Organized Collection of data and a set of operation on them is called data structure.
  3. File : If we think a unit of interrelated information or records is called file.
  4. Database : All structured data of a organization store in a computer system is called database.
There are four kinds of database
I)                   Hierarchical DBMS
II)                 Network DBMS
III)              Relational DBMS
IV)              Inverted DBMS
  1. Database Integrity: if data are interconnected with each other in the database is called data integrity.
  2.  Database redundancy : If homologues data are stayed in defferent place in the database is called database redundancy.
  3. Data Model : Data Model is a collection of same conceptual tools which describe data, data relationship, data semantics, and data constraints. data Model is main base of data structured.
 There are three types of data Model
I)                   Object based logical model
II)                 record base Logical Model.
III)              Physical Model
  1.   Relational Data Model: the Data Model  which use some table to express relation among data of record base logical model
  2. Data Schema : Overall design of database is called database schema
  3. Data Dictionary: After Compilation of data definition language we get a set of table. Those are stored in a file. This file is called data dictionary.
  4. Data Entity : Data Entity is some objects which has existence ad we can distinguish them form each other.
  5. Entity set : a Group of similar object which has similar properties.
  6. Primary key : An unique  identifier which identify the entity differently is called primary key.
  7. Formal Query Language : Formal Query Language is a language by which we can get procedural or non procedural benefit.
  8. Commercial Query Language: Commercial  Query Language is a language by which we can get procedural and non procedural benifit.
  9. Most Popular Query Language are:
I)                   SQL ( Structured Query Language)
II)                 QBE ( Query By Example)
III)              Quel ( ( Query Language)
IV)              Datalog.
  1. Several Parts of SQL
I)                   DDL (Data definition Language)
II)                 DML ( Data Manipulation Language)
III)              Embeded DML
IV)              View Definition
V)                Authorization
VI)              Integrity
VII)           Transaction Control
  1.  There are three clause of SQL
I)                   select
II)                 from
III)              where
  1. Aggregate function of SQL
I)                   average : avg
II)                 minimum : min
III)              Maximum: Max
IV)              Total : SUM
V)                Count : Count
  Server Database System : in this system data are stored centrally. this central computer is call server. This system is called client server system.
  1. Parallel Database system
  2. Distributed Database System

Some Computer Term

                                                                      
                                                                  Some Computer Term
  1.  OSI reference Model: OSI means Open System interconnection. it is a logical network Layer published by International Organization for Standardization and International  Telecommunication Union. it has seven layers such as application layer, presentation layer, session layer, transport layer, network layer, datalink layer, physical layer.

  1.    PC card : PC card is a Peripheral  card used for laptop card. it could be modem, network interface card etc.\

  1. ping : it is a command  to justify the connectivity of network. it use ICMP echo request massages to transfer them  to the specified workstation by the command.

  1.  POP3: Post office Protocol 3  is a TCP/IP Protocol work on application layer to use to receive e-mail from mail server to client.

  1. Remote Monitoring Protocol:  A network protocol that enables hardware and software devices to transmit status information to central network management console.

  1. Routing Information Protocol (RIP): A dynamic routing protocol that enables routers to receive information about others computer is the network. which enables them to keep their routing tables update.

  1. Secure Hyper Text Transfer Protocol (HTTPS) : A secure web Protocol that provides authentication and encryption services to Web client/ servers transactions

  1. Secure Socket Layer (SSL) : A secure web Protocol that provides authentication and encryption services to Web client/ servers transactions

  1. SLIP :Enhanment of SLIP is Serial line Internet Protocol. it is TCP/IP protocol of application layer used for dial up connections

  1. Simple Mail Transfer Protocol. (SMTP): An application Layer TCP/IP Protocol which is used for  sent Mail.

  1. SNMP: Simple Network Management Protocol is aprotocole which work on Application Layer TCP/IP Protocol used to transmit information about the status of network component to the CNMC 


  1. Telecommunication Network Protocol: (Telnet): An application layer protocol to administer remote computer.
  2. Transmission Control Protocol (TCP): it is a Transport layer connection oriented protocol.


  1.   user Datagram Protocol: An connectionless Transport layer Protocol use for short transaction, usually consisting a single request and reply.

  1. WINS Windows Internet Naming service: This service use for resolving NetBIOS Name to IP address.

  1. X.500: it is standard Published By ISO & ITU defining the structure of a global directory service. Windows Active Directory Service and Novell Directory service are based on X.500 structure

Necessary Terms of MCSA


multiple master replication : a technique usually associated with directory service, in which identical copies of database are maintained on various computer throughout the network.

MAU ( Multistation Access Unit) : a hub used in token ring network. this is more complicated than ethernet hub.  because instead of repeating incoming signals out through all port simultaneously, mau sends incoming signal through each port in trun.

 multitasking : A technique by which a computer with one processor executes multiple tasks simultaneously.      

  network access control : A hardware device used on wireless LANs employing the infrastructure topology to provide an interface between a cabled network and wireless network.

Modem : it is a network device which is need for modulation and demodulation. it make analog signal to digital and digital signal to analog signal.

 Port : A code number identifying the process running on a TCP/IP computer.  transport layer protocol such as TCP and UDP specify The port number of the source and destination application processes in the header o
f each massage they create.

       PROTOCOL: An ASCII Text file found TCP/IP systems that lists the codes used in teh Protocol field on the Internet Protocol(IP) header.

 Proxy server:  Proxy server is a server by which unregistered IP can access to the internet. The proxy server must has a registered IP,

redirector :  A network client component that determines whether a resource requested by an application is located on the network or on the network.

Remote Bridge: A network device operating on data link layer of the OSI reference model  which is connect to Lan at different location with a WAN link. 

 Repeater : repeater is a network device which amplifies network signal enabling them to travel longer distance without suffering for effect of attenuation.

routing table: 

schema : schema is the structure of directory service . such as Active directory in Microsoft Domain Controller, NDS in Novel Network.

services :  services is a windows term to do  special task, such (DNS) Donain name service is for name resolving. spooler is for print share etc.

SERVICES : a ASCII test file which contain the codes used  in the source port and destination port fields of the TCP and UDP header.

Small computer system interface (SCSI) : a Peripheral Device Interface which enable you to connect internal and extarnal device to a computer.

Windows Domain and Communication Process


Directory service: A database containing about network entities and resource. Such as active directory for windows 2000 server, bindery for novel Net Ware.

Domain :Domain is a groups of workstation and other devices on a network that are administrated as a single unit.

Domain controller: A computer configured by  windows 2000/2003/2007 that is designated to store and manage directory services information.\

Domain Name service: an service which map IP address to Domain name.

 Driver :  a software by which operation system communicate with hardware.

DHCP : Dynamic Host configuration Protocol is a service which provide IP address to the network automatically.

Dynamic Routing : by this routing systems router builds  a routing table automatically by specialized protocol.    

EIA/TIA: Electrical Industry Association/ Telecommunication Industry Association

FDDI : Fiber Distributed Data interface

fiber Optic: a network cable use a technology that uses light to send signal  rather than electrical charge use by copper cables.

FTP : File Transfer protocol, work application layer on OSI systems

Full Duplex: a form of network communication in which to connected systems can send signals at a time such telephone line.

Half Duplex: a form of network communication in which to connected systems can send signals in one direction at a time such as radio

Hops : In an internetwork each router is a hop.

hosts : An ASCII text file which is used by TCP/IP computer to resolve host name to IP address.

Hub : Hub is a network device which is used in star network  topology to connect the computer with each other.

 IPCONFIG : a command line utility to know the ip configuration of a computer.

 incremental Backup :  incremental Backup systems is a  backup systems by which we can backs up which was modified or created after the last incremental or full backup. this systems sets archives bit.

IEEE : International Electrical and Electronic  Engineers: A organization formed on 1984 which is dedicated to development and publication of standard for the computer and electronics industries

Network tips


circuit switching : it is one kinds of network communication   in which two communicating systems established a connection that remains open through out the life of transaction . the telephone network is the example of circuit switching network.

Packet switching : a type of network communication where both systems does no established the handshake before transmitting data.

cluster : a group of two or more servers computers connected togather so theat they function as a single unified resource, for purpose of fault tolerance, load balancing and parallel processing.

collision : in local area network if two computer send data same time to one another, causing loss data. It is called collision.

connection less : a type of protocol that transmit data without establishing connection with destination systems. Such IP ( Internet Protocol), UDP  ( user datagram protocol)

connection oriented : a type of protocol that established connection with destination systems  before transmitting data . Such TCP ( Tramsmission Control Protocol), NETBUEI etc.

D channel : A digital communication channel running 16 or 64 kbps that is one of the fundamental unit of services provided by ISDN

default gateway: The  router on the local network used by TCP/IP client network to transmit data to another network.

Differential backup: by this type of backup backs up the file which changed after the full backup.

Enhancement of Some Important computer Term



HCL: Hardware compatibility List: A list of Hardware which was tested by windows 2000
NTFS (New Technology File system): it is new Technology File system by which we can configure local security and domain security and we can input permission any user individually.                                                                                                                                                                                                                                                                                                                   
FAT16: 16 bit file allocation Table widely used in DOS, win3x, disadvantage of this system is that it only support partition  2GB , it support almost all operating systems.
FAT32: 32 bit file allocation table first introduced 1996 with windows 1996.   this system is that it only support partition  as large as 2TB.
windows NT and earlier released of NT does not support FAT32.
 ACPI: Advance Configuration and Power Interface: The automatic and dynamic detection of hardware that is installed. the ability to determined what hardware resource are required for the device.
IEEE: Institute of electrical and Electronic engeneers.1394 slandered
which support data transfer at speeds up to 400Mbps.
Hot swap: this is a process by which we can add a new hard drive while the computer on.
RG -58 Ethernet : 10 base 2 cabel which radius is .195  that use BNC ( Bayonet Neill Concilman) connector
RG -8 Ethernet : 10 base 5 cable which radius is .405 That use N connector.
STP : (Shielded Twisted pair):  It use in token ring network. it’s connector is called IDC(IBM Data Connector)
LED : Light Emitting Diode.
UTP ( Unshielded Twisted pair :  It has four fair, two pair is use to pass data. it’s maximum length is 100 meter.
Hub :  Ethernet hub is called a multiport repeater , it is a physical layer device.
Repeater : This is a network device which amplify the signal as it pass through it.
MAU : Multi Access Unit: it is a network device used in Token ring network.
Switch : Switch is a network device which works at data link layer of OSI model. it is upgraded from hub.
Router : Router connect two network together forming an internetwork. router function at network layer of OSI Model.
Protocol suit : Combination of two Protocol is called protocol suit.
Novel NetWare : Novel NetWare is the first network system of the world.
FDDI : Fiber Distributed Data Interchange.   

Info of Database Adminstrator

Database Manager
Database Administrator: The mean who contort data program and data structure centrally is called database administrator. The following are his duty.
    1. Schema Definition
    2. Storage structure and access method
    3. Schema and physical organization modification
    4. Granting of authorization for data access.
Entity: Entity is object which has existence and which is distinguish from one another.
Entity set: Entity Set is collection of similar entity which has similar properly or attribute.
Relationship: Relationship is association of among entity.
Primary Key: The unique identifier by which we can identify entity differently from entity set.
Super Key:
Network Data Model : The data model which is express by collection of records and relation is represented links is called network data model. It do not support many to one relationship.
Hierarchical Data model: The data model which is express by collection for records and relation is represented links is called hierarchical Data model. It support to one relationship.
  • Data Structure Diagram: Data Structure diagram is the schema of network data model.
  • Tree structure Diagram: Tree structure diagram is the schema of hierarchical Data model.
  • Relational Data Model: The Data model which represent data by collection of table is called relational data model.
The following are database system:
  1. Server database system
  2. Client server database system
  3. Distributed database system.

Topology



The logical and physical collection of computer in a network is called  topology .Topology means now a days physical topology .
Classifications are :
a.      Bus topology
b.      Ring  topology
c.       Star topology
d.      Tree topology
e.       Mesh topology
f.        Hybridge topology
Bus
In a bus topology all computers are connected to a central cable called bus or backbone.
Star
A star topology is intended with each node (file server, workstations, and peripherals) connected straightforwardly to a central network Devices. Data on a star network passes through the network Devices before continuing to its destination. The network Devices manages and controls all functions of the network. It also acts as a repeater for the data flow. This configuration is common with twisted pair cable. Though, it can also be used with coaxial cable or fiber optic cable
Ring
A ring topology may show to be the same as a star topology. on the inside, the MAU (multistation access unit) of a ring contains wiring that allows information to pass from one device to another in a circle or ring . The Token Ring protocol uses a ring topology.
 Tree                                                     
A tree topology is the combination of characteristics of linear bus and star topologies. It consists of groups of star-configured workstations linked to a linear bus backbone cable. Tree topologies permit for the extension of an existing network, and enable  to configure a network to meet their needs.