Page 314 - IT 402 v2.0 class 10
P. 314

.  Identify any two  olumn name  ttribute and their data types from a given table:
                                                      T able : PL A Y ER

                                  PID     PNAME       RUNS       GENDER          DOB
                                 P101    S   IN       13000         M         10/04/2001
                                 P102       I          7000         M         12/02/1998
                                 P103    S            12000         M         13/04/2001

                                 P104     I           12500         M         17/03/2005
         Ans.  Column name/Attribute          D a t a   t y p e
                   N M
                    NS                        IN
          15.  ............................. statement is used to add one or more records to a database.
         Ans.  I N S E R T

          16.  ............................. statement retrieves  ero or more rows from one or more database tables.
         Ans.  S E L E C T

            .   xplain two types of languages used for creating and manipulating the data in databases.
         Ans.      ata   efinition   anguage  or   ata   escription   anguage         is  a  standard  for  commands  that  define
              the  different  structures  in  a  database.       statements  create   modify  and  remove  database  ob ects  such  as
              tables  indexes and users.  ommon     statements are                   N        N M  and   O .  ata
              Manipulation  anguage   M
                   ata Manipulation language   M   is a language that enables users to retrieve  update  insert and delete data
              in a database.  ommon  M  statements are S               INS    IN O and       .
            .   xplain any three data types in OpenO ce  ase.

          ns.  i.  Numeric  ata  ype   ii.  lphanumeric Data Type   iii. Date/Time Data Type
            .   xplain the following with respect to  atabases :
               a   Forms                                        b   eports
               c    able                                        d   hat is a primary key
               e    ategorise the following commands as     and  M :

                                               S              INS       O
         Ans.  a.  Forms: Forms enable to provide a user interface for entering of data or to display intermediary information. In
                the Form, the user can add or modify data.
              b.  Reports: A report summarizes or displays the information in a format that is suitable for viewing or publishing.
                 eports are used to present the results in a meaningful and useful manner.  eports can obtain information
                from tables or  ueries.  eports are printed to share information.
              c.  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.
              d.  Primary Key:  rimary key is a field which is used to uni uely identify records in a database. It is a uni ue field
                and it cannot be left blank. There can be only one primary key in a table. If there are more than one primary keys,
                then there will be two identities against a row.  here can be only one identity against a row. So  we cannot have
                more than one primary key. To make retrieval of records faster, Primary keys are indexed in database.
              e.  DDL:          O
                DML: S       INS




         312       Touchpad Information Technology-X
   309   310   311   312   313   314   315   316   317   318   319