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package sikshapath; //create your own package
import java.util.*;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Scanner;

class EmailId
{

    String domainID,username,password;

    EmailId()
    {
        domainID="K7";
        username="K";
        password="constructc000";
    }

    EmailId(String user,String pass,String domID)
    {
        domainID=domID;
        username=user;
        password=pass;
    }

    public static void main(String[] args) {
        String user,pass, domID;
        int p=-1,up=-1,u=-1,d=-1;

        EmailId obj=new EmailId();

        Scanner sc= new Scanner(System.in);
        System.out.println("Enter username: ");
        user=sc.nextLine();
        System.out.println("\nEnter password: ");
        pass=sc.nextLine();
        System.out.println("\nEnter Domain ID: ");
        domID=sc.nextLine();
        System.out.println("Enter a date in dd/mm/yyyy format :");
        String date = sc.next();

        EmailId obj1=new EmailId(user,pass,domID);

        if((obj.username).equals(obj1.username))
        {
            u=1;
            if(obj.password.equals(obj1.password))
            {
                up=1;
            }
            else
            {
                p=0;
            }
        }
        else
        {
            u=0;
        }

        if(dateValidation(date)==true)
            d=1;
        else
            d=0;

        if(d==1)
        {
            if(u==0)
            {

                try{
                    throw new InvalidUsernameException(user);
                }

                catch (Exception e) {
                    System.out.println(e) ;
                }
            }

            if (p==0){
                {
                    try{

                        throw new InvalidPasswordException(pass);
                    }
                    catch (Exception e) {
                        System.out.println(e) ;
                    }
                }
            }

            if(up==1)
            {
                System.out.println("Valid email id");
            }
        }
        else{
            System.out.println("Not a Valid email id");
        }

    }

    public static boolean dateValidation(String date)
    {
        boolean status = false;

        if (checkDate(date)) {
            DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
            dateFormat.setLenient(false);
            try {
                dateFormat.parse(date);
                status = true;
            } catch (Exception e) {
                status = false;
            }
        }
        return status;
    }

    static boolean checkDate(String date) {
        String pattern = "(0?[1-9]|[12][0-9]|3[01])\\/(0?[1-9]|1[0-2])\\/([0-9]{4})";
        boolean flag = false;
        if (date.matches(pattern)) {
            flag = true;
        }
        return flag;

    }



}

class InvalidUsernameException extends Exception{
    String num1;
    InvalidUsernameException(String num2) {
        num1=num2;
    }
    public String toString(){
        return ("exception in thread ‘main’ InvalidUsernameException: Username: "+ num1 + " doesn’t match") ;
    }
}

class InvalidPasswordException extends Exception{
    String num1;
    InvalidPasswordException(String num2) {
        num1=num2;
    }
    public String toString(){
        return ("exception in thread ‘main’ InvalidPasswordException: Username: "+ num1 + " doesn’t match") ;
    }
}

1.What is a database?
a) Organized collection of information that cannot be accessed, updated, and managed
b) Collection of data or information without organizing
c) Organized collection of data or information that can be accessed, updated, and managed
d) Organized collection of data that cannot be updated

2.What is DBMS?
a) DBMS is a collection of queries
b) DBMS is a high-level language
c) DBMS is a programming language
d) DBMS stores, modifies and retrieves data

3.Who created the first DBMS?
a) Edgar Frank Codd
b) Charles Bachman
c) Charles Babbage
d) Sharon B. Codd

4.Which type of data can be stored in the database?
a) Image oriented data
b) Text, files containing data
c) Data in the form of audio or video
d) All of the above

5.Which of the following is not a type of database?
a) Hierarchical
b) Network
c) Distributed
d) Decentralized

6.Which of the following is not an example of DBMS?
a) MySQL
b) Microsoft Acess
c) IBM DB2
d) Google

7.Which of the following is a feature of DBMS?
a) Minimum Duplication and Redundancy of Data
b) High Level of Security
c) Single-user Access only
d) Support ACID Property

8.Which of the following is known as a set of entities of the same type that share same properties, or attributes?
a) Relation set
b) Tuples
c) Entity set
d) Entity Relation model

9.What is information about data called?
a) Hyper data
b) Tera data
c) Meta data
d) Relations

10.What does an RDBMS consist of?
a) Collection of Records
b) Collection of Keys
c) Collection of Tables
d) Collection of Fields

 11.The values appearing in given attributes of any tuple in the referencing relation must likewise occur in specified attributes of at least one tuple in the referenced relation, according to _____________________ integrity constraint.
a) Referential
b) Primary
c) Referencing
d) Specific

12._____________ is a hardware component that is most important for the operation of a database management system.
a) Microphone
b) High speed, large capacity disk to store data
c) High-resolution video display
d) Printer

13.The DBMS acts as an interface between ________________ and ________________ of an enterprise-class system.
a) Data and the DBMS
b) Application and SQL
c) Database application and the database
d) The user and the software

14.______________ is a set of one or more attributes taken collectively to uniquely identify a record.
a) Primary Key
b) Foreign key
c) Super key
d) Candidate key

15.Which of the following set should be associated with weak entity set for weak entity to be meaningful?
a) Neighbour set
b) Strong entity set
c) Owner set
d) Identifying set

16.Which forms have a relation that contains information about a single entity?
a) 4NF
b) 2NF
c) 5NF
d) 3NF

17.The top level of the hierarchy consists of ______ each of which can contain _____.
a) Schemas, Catalogs
b) Schemas, Environment
c) Environment, Schemas
d) Catalogs, Schemas

18._______ indicates the maximum number of entities that can be involved in a relationship.
a) Greater Entity Count
b) Minimum cardinality
c) Maximum cardinality
d) ERD

19.The user IDs can be added or removed using which of the following fixed roles?
a) db_sysadmin
b) db_accessadmin
c) db_securityadmin
d) db_setupadmin

20.Why the following statement is erroneous?

SELECTdept_name, ID,avg(salary)

FROM instructor

GROUPBYdept_name;

1. a) Dept_id should not be used in group by clause
   b) Group by clause is not valid in this query
   c) Avg(salary) should not be selected
   d) None

21.Which of the following is not the utility of DBMS?
i) Backup ii) Loading iii) Process Organization iv) File organization
a) i, ii, and iv only
b) i, ii and iii only
c) i, iii and iv only
d) All i, ii, iii, and iv

22.What is the function of the following command?

Delete from r where P;

1. a) Clears entries from relation
   b) Deletes relation
   c) Deletes particular tuple from relation
   d) All of the mentioned

23.Which of the following is popular for applications such as storage of log files in a database management system since it offers the best write performance?
a) RAID level 0
b) RAID level 1
c) RAID level 2
d) RAID level 3

24.Which of the following represents a query in the tuple relational calculus?
a) { }{P(t) | t }
b) {t | P(t)}
c) t | P() | t
d) All of the mentioned

25.Evaluate the statements issued by the DBA in the given sequence if OE and SCOTT are the users and the ORDERS table is owned by OE.

CREATEROLE r1;GRANTSELECT,INSERTONoe. orders TO r1;GRANT r1 TOscott;GRANTSELECTONoe. orders TOscott;REVOKESELECTONoe.ordersFROMscott;

What would be the outcome after executing the statements?
a) The REVOKE statement would give an error because the SELECT privilege has been granted to the role R1
b) The REVOKE statement would remove the SELECT privilege from SCOTT as well as from the role R1
c) SCOTT would be able to query the OE.ORDERS table
d) SCOTT would not be able to query the OE.ORDERS table