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MS is used to build the database and also manage the databases in different ways like:

               dding new records  appending
               diting  changing modifying the existing data
               eleting  removing unwanted data
              Sorting  arranging in an order  ascending descending

              Extracting the data based on queries
              Updating and manipulating data items
              Viewing data and generating reports
              Performing calculations on it, etc.
                MS allows various  user application programs to simultaneously  access the same database. Most popular
              MSs include Oracle  I M      Microsoft S   Server  Microsoft  ccess   ostgreS    MyS    Fox ro  and
            S  ite.

            Data can be organised into two types:

              Flat File:  ata is stored in a single table. It is mainly suitable for less volume of data.
              Relational: In relational files  data is stored in multiple tables and the tables are linked using a common
              field.  elational is suitable for medium to large volume of data.

            Database Servers

             atabase servers are dedicated computers that can  hold the actual databases. It can  run only the   MS
            and its related software. Databases available on the database servers are accessed through command-line or
             raphic  ser Interface tools also called as Frontends. Other servers are referred to as  ackends that process
            the request and provide the data. These servers are based  on client-server model or architecture.
                      N ot e s

                       ho governs the  atabase Management S ystem
                       ho governs the  atabase Management S
                                                            ystem
                       ho governs the  atabase Management System
                      The person having the centralised control over the database system is called the Database Administrator.
                      The person having  the centralised  control  over  the database  system is called the Database  Administrator.
                                                               the database
                      The person having
                                       the centralised
                                                    control
                                                           over
                                                                           system is called the Database
                                                                                                      Administrator.
                                                                                                      management
                                                          who
                                                          who
                                                                                                      management
                                              is an IT expert
                                              is an IT expert
                                                                                                   and
                                                                             the technical operations
                                                              is responsible for
                                                                             the technical operations
                                                              is responsible for
                                                                                                   and
                      The database
                      The database
                      The database administrator is an IT expert who is responsible for the technical operations and management
                                  administrator
                                  administrator
                      of database.
                      of database.
               ELEMENTS OF DATABASE
            Data in a   MS package is generally kept in a tabular format and is organised by fields  records and files.
            A field represents a single type of related information; a record is a complete set of values stored under
            fields  whereas a file is a collection of records and the records are kept in a table.
              Table: A table is a collection of logically related records. The multiple records of a database are arranged
              together in a tabular structure to make a table. It is made of rows and columns.
               enerally  a column represents a field which contains information of a particular type  whereas a row
              represents records which contain information of the related fields.
              Field:   field represents one related part of a table. It contains the logically related data contained in a
              database. For example  age  name   address  designation and phone are fields in the table given below.
              Record:   record is a collection of multiple data which is stored in related fields that can be treated as a single
              unit. It represents the data which is entered in a set of different fields which are related to a particular item.
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