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7.  Which of the following queries will give the same output:                   [CBSE Sample Paper 2023]
              i.   select rollno, name from student where subject in (‘information Technology’,’informatics
                practices’);
              ii.  select rollno, name from student where subject between ‘information Technology’
                and ‘informatics practices’;
              iii.  select rollno, name from student where subject =’information Technology’ or subject
                =’ informatics practices ‘;
              iv.  select rollno, name from student where subject =’information  Technology’  and
                subject =’informatics practices’;
         Ans.  i and iii are same
           8.  Rema wants to input the price of shoes as 999.99 .What should be the datatype and size of the
             column price in the table?                                                    [CBSE Sample Paper 2023]
         Ans.  Decimal (5,2)
           9.  What is the MYSQL command to list the names of teachers in alphabetical order in the teacher
             table?                                                                        [CBSE Sample Paper 2023]
         Ans.  SELECT Name
              FROM Teacher
              ORDER BY Name;
          10.  Write the command to see the structure of a table?                          [CBSE Sample Paper 2023]
         Ans.  DESCRIBE
          11.  List any two advantages of DBMS.                                            [CBSE Sample Paper 2023]
         Ans.  Reduction in Redundancy, Improved Consistency
        B.  Long answer type questions.
           1.  What are the types of users of DBMS?
         Ans.  The types of users of DBMS are as follows:
             Ð   End Users: Users who use the database for querying, modifying and generating reports as per their needs. They are not
                concerned about the working and designing of the database. They simply use the DBMS to get their task done.
             Ð  Database Administrator (DBA): As the name implies, the DBA administers the database and the DBMS. The DBA is responsible
                for authoring access, monitoring its use, providing technical support and acquiring software & hardware resources.
             Ð  Application Programmers: Application programmers write application programs to interact with the database. These
                programs are written in high-level languages and SQL to interact with the database.
             Ð  System Analyst: The system analyst determines the requirements of the end-users and then develops specifications to
                meet these requirements. A system analyst plays a major role in the database design and all the technical, economic and
                feasibility aspects.
           2.  Mention the advantages of using DBMS approach.
         Ans.  The advantages of using DBMS approach are as follows:
             Ð  Reduction in Redundancy: Data in a DBMS is more concise because of the central repository of data. All the data is stored
                in one place. There is no repetition of the same data. This also reduces the cost of storing data on hard disks or other
                memory devices.
             Ð  Improved Consistency: The chances of data inconsistencies in a database are also reduced as there is a single copy of
                data that is accessed or updated by all the users.
             Ð  Improved Availability: Same information is made available to different users. This helps sharing of information by various
                users of the database.
             Ð  Improved Security: Though there is improvement in the availability of information to users, it may also be required to
                restrict access to confidential information. By making use of passwords and controlling users’ database access rights, the
                DBA can provide security to the database.
             Ð  User Friendly: Using a DBMS, it becomes very easy to access, modify and delete data. It reduces the dependency of users
                on computer specialists to perform various data related operations in a DBMS because of its user-friendly interface.
           3.  Mention any two limitations of using DBMS approach.
         Ans.  Two limitations of using DBMS approach are as follows:

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