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SQL and Relational Databases 101 Cognitive Class Exam Answers:-

Course Name:- SQL and Relational Databases 101

Modules 1. SQL and relational Dtabase 101

Question 1. What is a Database?

  • A program that stores data
  • Stores data in tabular form
  • A repository of data
  • All of the above

Question 2. Advantages of the relational model include:-

  • Provides logical and physical data independence
  • Data is stored in simple data structures
  • It is the most used data model
  • All of the above

Question 3. In an Entity-Relationship diagram, the Entity Name maps to the Table name, the attributes map to the …

  • Table rows and columns
  • Table columns
  • Table rows
  • None of the above

Modules 2. Relational Model constraints and data objects

Question 1. Which of the following statements is true?

  • A table can have a primary key and a foreign key
  • A Foreign Key is a set of columns referring to a primary key of another table
  • A primary key uniquely identifies each row in a table
  • All of the above

Question 2. Which Relational Constraint prevents duplicate values in a table?

  • Entity Integrity constraint
  • Null constraint
  • Check constraint
  • All of the above

Question 3.The Semantic Integrity Constraint defines the relationships between tables. (T/F)

  • True
  • False

Modules 3. Data definition language (DDL) And Data Manipulation language(DML)

Question 1.The Primary Key of a relational table uniquely identifies each _____ in a table.

  • column
  • row
  • Both of the above
  • Neither of the above

Question 2. The INSERT statement cannot be used to insert multiple rows in a single statement. (T/F)

  • True
  • False

Question 3. The SELECT statement is called a Query, and the output we get from executing the query is called a Result Set.

  • True
  • False

Modules 4. Advanced DDL and DML

Question 1. You want to select an author’s name from a table, but you only remember the author’s last name starts with the letter B, which string pattern can you use?

  • SELECT lastname from author where lastname like ‘B$’
  • SELECT lastname from author where lastname like ‘B%’
  • SELECT lastname from author where lastname like ‘B#’
  • None of the above

Question 2. In a SELECT statement, which SQL clause controls how the result set is displayed?

  • ORDER BY clause
  • ORDER IN clause
  • ORDER WITH clause

Question 3.Which SELECT statement eliminates duplicates in the result set?

  • SELECT country from author ORDER BY 1
  • SELECT distinct(country) from author
  • SELECT unique(country) from author
  • None of the above

Module 5. Working With multiple Tables

Question 1.  An INNER JOIN returns only the rows that match. (T/F)

  • True
  • False

Question 2. A LEFT OUTER JOIN displays all the rows from the right table, and combines matching rows from the left table. (T/F)

  • True
  • False

Question 3.When using an OUTER JOIN, you must explicitly state that you want either a LEFT JOIN or a RIGHT JOIN. (T/F)

  • True
  • False

SQL and Relational Databases 101 Cognitive Class Final Exam Answers:-

Question 1. The 5 basic SQL commands are…

  • CREATE, SELECT, INSERT, UPDATE, DELETE
  • CREATE, ALTER, INSERT, UPDATE, DELETE
  • CREATE, SELECT, INSERT, MODIFY, DELETE
  • All of the above

Question 2. The blueprint of any database system is the …

  • Data model
  • Information model
  • Both of the above

Question 3. Attributes help clarify relationship diagrams (T/F)

  • True
  • False

Question 4. A table containing one or more foreign keys is called a Parent table. (T/F)

  • True
  • False

Question 5. The Referential Integrity Constraint ensures the validity of the data using a combination of Primary Keys and Foreign Keys.

  • True
  • False

Question 6. What are the basic categories of the SQL language based on functionality?

  • Data Manipulation Language
  • Data Definition Language
  • Both of the above
  • Neither of the above

Question 7. The CREATE TABLE statement is a….

  • DDL statement
  • DML statement
  • Both of the above

Question 8. When using the UPDATE statement, if you do not specify the WHERE clause, all the rows in the table are updated.

  • True
  • False

Question 9. You want to select a list of books whose number of pages is between 100 and 200 . Select the correct query from the following options.

  • SELECT title, pages from book where pages BETWEEN 100 AND 200
  • SELECT title, pages from book where pages RANGE 100 AND 200
  • SELECT title, pages from book where pages less than or equal to 100 AND pages greater than or equal to 200
  • A or B
  • All the options above are correct

Question 10. What is the default sorting mode of the ORDER BY clause?

  • Ascending
  • Descending
  • Randomly selected order
  • None of the above
  • All of the above

Question 11. Which of the following can be used in a SELECT statement to restrict a result set?

  • HAVING
  • GROUP BY
  • DISTINCT
  • All of the above

Question 12. The HAVING clause works only with the GROUP BY clause. (T/F)

  • True
  • False

Question 13. Which of the following are valid types of OUTER JOIN?

  • LEFT OUTER JOIN
  • RIGHT OUTER JOIN
  • FULL OUTER JOIN
  • A and B only
  • All of the above

Question 14. A FULL JOIN returns only the rows that match. (T/F)

  • True
  • False

Question 15. To combine tables in relational databases , we use:

  • Table names
  • Matching values/Primary key
  • Tables cannot be combined
  • None of the above options are correct

Question 16. >> True or False: Semantic integrity ensures that data entered into a row reflects an allowable value for that row.

  • True
  • False

Question 17. Which of the following statements are correct about databases :

  • A database represents some aspect of the real world
  • A database is a logically coherent collection of data with some inherent meaning
  • A database is designed, built and populated with data for a specific purpose
  • All the above options are correct

Question 18. Which of the following statements are correct about primary keys

  • The value of the Primary Key must be unique for each instance of the entity.
  • There can be no missing values( ie. Not Null) for Primary Keys.
  • The Primary Key is immutable.i.e., once created the value of the Primary Key cannot be changed.
  • All the above options are correct

Question 19. The ____________ keyword is used to eliminate duplicate tuples from the result set of an SQL query.

  • COMMON
  • DISTINCT
  • ALL
  • EXISTS

Question 20. Select the correct statements about the join operator

  • PrimaryKey- ForeignKey is the common join operator
  • Is used to combine more than one table
  • You have to know the relationship between the tables
  • None of the statements are correct

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