INFS22007903 PROJECT 5 ASSIGNMENT Solution

The goal of this project is to gain practical experience in applying several database management concepts and techniques using the Oracle DBMS.

Your main task is to first populate your database with appropriate data, then design, implement, and test the appropriate queries to perform the tasks explained in the next sections.


Roadmap: Section 1 describes the database schema for your project and it also provides instructions on downloading the script file needed to create and populate your database. Section 2 describes the tasks to be completed for this project. Finally, Section 3 provides you with all the necessary submission guidelines.

Enjoy the project!

-----------------

SECTION 1. THE MOVIES DATABASE


The Database: The MOVIES database (Figure 1) captures the information regarding movies and the actors in these movies. The database includes six tables: film, actor, category, language, film_actor, and film_category. Film keeps track of film details. Actor stores information about all actors in the movie industry. Category stores the information about the different types of film categories. Language stores the different languages in which these movies are released. Film_actor and film_category keep track of which actors have acted in which films, and which films are classified under which categories, respectively.


Figure 1 Database schema


The Script File: Please go to Blackboard and download the supplementary script file for this project “prjScript.sql”.

The Database Constraints: The following table lists all the constraints that should be created on the MOVIES database.

No Constraint Name Table.Column Description
1 PK_ACTORID actor.actor_id actor_id is the primary key of actor
2 PK_CATEGORYID category.category_id category_id is the primary key of category
3 PK_FILMID film.film_id film_id is the primary key of film
4 PK_LANGUAGEID language.language_id language_id is the primary key of language
5 UN_DESCRIPTION film.description Film description values are unique
6 CK_FNAME actor.first_name Actor’s first name must not be empty (not null)
7 CK_LNAME actor.last_name Actor’s last name must not be empty (not null)
8 CK_CATNAME category.name Category name must not be empty (not null)
9 CK_LANNAME language.name Language name must not be empty (not null)
10 CK_TITLE film.title Film title must not be empty (not null)
12 CK_RATING film.rating Rating type must be one of the following: 'G', 'PG', 'PG-13', 'R', 'NC-17'
13 CK_SPLFEATURES film.special_features Special features type must be either empty or one of the following: 'Trailers',
'Commentaries', 'Deleted
Scenes', 'Behind the Scenes'
14 FK_LANGUAGEID film.language_id and language.language_id film.language_id refers to language.language_id
15 FK_ORLANGUAGEID film.original_language_id and language.language_id film.original_language_id refers to language.language_id
16 FK_ACTORID film_actor.actor_id and actor.actor_id film_actor.actor_id refers to actor.actor_id
17 FK_CATEGORYID film_category.category_id and category.category_id film_category.category_id refers to category.category_id
18 FK_FILMID1 film_actor.film_id and film.film_id film_actor.film_id refers to film.film_id
19 FK_FILMID2 film_category.film_id and film.film_id film_category.film_id refers to film.film_id

Table 1. Database constraints

-----------------

SECTION 2. ASSIGNMENT TASKS


Create and Populate Database: You need to execute the script file “prjScript.sql” to create and populate your database before working on the following tasks. Wait till you see the message “DONE! All data has been inserted.” It should only take one minute. The script will also drop related tables.


Task 1 – Constraints

Question: Which constraints in Table 1 have been created on these six tables?

2. Write the SQL statements to create all the missing constraints.


Task 2 – Triggers

1. Assume that the film_id should be automatically populated when a new film is added. Write a SQL statement to create a sequence object to generate values for this column. The sequence, named FILM_ID_SEQ, should start from 20,010 and increment by 10.

2. Write a SQL statement to create an Oracle trigger called BI_FILM_ID that binds the sequence object FILM_ID_SEQ to the film_id column, i.e., the trigger populates values of FILM_ID_SEQ to the film_id column when a new film is added.

3. Write a SQL statement to create an Oracle trigger BI_FILM_DESP that appends text to the description of every new film inserted into the database. The text is based on the rating, the language, and the original language of the film. The format of the text you append should be as follows (replacing tokens):

<rating>-<seq>: Originally in <original language>. Re-released in <language>.

Here, <seq> is the sequence number of the film with that <rating>, and <original language> and <language> should be the name of the language from the language table.

Hint: You might need to use some built-in functions for string manipulation such as TO_CHAR, CONCAT, SUBSTR, INSTR, etc.

Example: Assume the following film is inserted into the database, which is the
5th film with a rating ‘PG’ (i.e., there are already 4 films with the rating ‘PG’ in the database), and the current FILM_ID_SEQ value is 20,010.

INSERT INTO film (title, description, language_id, original_language_id, rating) VALUES (‘B Movie’, ‘Movie about wasps.’, 1, 2, ‘PG’);

It should produce the following result when the following SQL statement is run:

SQL> SELECT description FROM film WHERE film_id = 20010;

DESCRIPTION
-----------------------------------------------------------------------------------------
Movie about wasps.PG-5: Originally in Italian. Re-released in English.


Notes for Task 2.3:
• The new description must match the expected output exactly in order to receive marks. For example, o Do not add extra space or line break; o Do not change capitalisation of the rating or the language names.
• If either rating, language_id, or original_language_id of the new film is null, then the trigger should do nothing, i.e., the new film uses the original description.
• You do not need to handle the cases where the resulting text after the trigger exceeds the description length. Let the trigger fail.
• Do not use hardcode. Your trigger should be able to handle other languages beyond those provided to you in the SQL script. o For example, if the language ‘SQL’ is added to the language table, then the trigger should be able to handle a movie in ‘SQL’.


Task 3 – Views

1. Write a SQL statement to find the ‘Action’ (category) films with the shortest running time (length). Your query should output the titles and lengths of the films.


3. Write a SQL statement to create a (virtual) view called V_ACTION_ACTORS_2012 that lists the ids, first names and last names of all the actors who have acted in an ‘Action’ film released in the year 2012. (Note: There should be no duplicate rows in the view, similar to Task 3.2)
4. Write a SQL statement to create a materialized view MV_ACTION_ACTORS_2012 that lists the same information as in Task 3.3.

5. Execute the following two SQL statements and report their query execution time. Question: Did the materialized view speed up the query processing? Explain your answer. (Hint: You should look at both the elapsed time and the cost in the query execution plan)

SELECT * FROM V_ACTION_ACTORS_2012; SELECT * FROM MV_ACTION_ACTORS_2012;

Note: For any task mentioning the execution time, please run the queries on a computer with a HDD rather than an SSD, so that the timing difference is noticeable. All lab computers have HDDs and are appropriate for such task.


Task 4 – Indexes

1. Write a SQL statement to find the first 100 films (in ascending alphabetical order of the film titles) that take place in a ‘Boat’, i.e., the word ‘Boat’ appears in the film description. (Note: You should avoid using LIKE in the SQL statement and instead use string manipulation functions)

2. In order to potentially speed up the query in Task 4.1, a function-based index could be created on the film table. Write a SQL statement to create an index IDX_BOAT that best fits the task and justify your choice.

3. Report the execution time and execution plan of the query statement you wrote in Task 4.1 before and after creating the index in Task 4.2.
Question: Did the index speed up query processing? Explain your answer. (Hint:
You should look at both the elapsed time and the cost in the query execution plan)

4. Write a SQL statement to count the number of films for which there are at least 40 other films with the same release_year, rating, and special_features values.

5. In order to potentially speed up the query in Task 4.4, indexes should be created on the release_year, rating, and special_features columns.
Question: In your opinion, what is the most suitable index type to create on those columns, and why? (Note: Do not include any SQL to create the index in your script file; just provide your answer in the report)


Task 5 – Execution Plan

1. A B+ tree index PK_FILMID has been generated automatically for the primary key film_id of the table film. Write SQL statements to answer the following Questions:
• What is the height of the B+ tree index?
• What is the number of leaf blocks in the B+ tree index?
• What is the number of block access needed for a full table scan of the film table?

• https://docs.oracle.com/cd/B28359_01/server.111/b28320/statviews_5119.ht m#REFRN29025
• https://docs.oracle.com/cd/B19306_01/server.102/b14237/statviews_4473.ht m#REFRN26286
• https://docs.oracle.com/cd/B19306_01/server.102/b14237/statviews_2105.ht m#REFRN20286

2. The following SQL statement lists all the films with a film_id larger than 100:

SELECT * FROM FILM WHERE FILM_ID > 100;

Report the rule-based execution plan chosen by the Oracle optimizer for executing this query.
Question: Explain the query processing steps taking place in this plan.

3. Report the cost-based execution plan chosen by the Oracle optimizer for executing the query in Task 5.2.
Question: Explain the query processing steps taking place in this plan. In your opinion, what are the main differences between the plans you obtained in Task 5.2 and Task 5.3, based on the statistics from Task 5.1 and your calculation?

4. The following SQL statement lists all the films with a film_id larger than 19,990:

SELECT * FROM FILM WHERE FILM_ID > 19990;

Report the cost-based execution plan chosen by the Oracle optimizer for executing this query.
Question: Explain the query processing steps taking place in this plan. In your opinion, what are the main differences between the plans you obtained in Task 5.3 and Task 5.4, based on the statistics from Task 5.1 and your calculation?

5. The following SQL statement lists all information for the film with a film_id of 100:

SELECT * FROM FILM WHERE FILM_ID = 100;

Report the cost-based execution plan chosen by the Oracle optimizer for executing this query.
Question: Explain the query processing steps taking place in this plan. In your opinion, what are the main differences between the plans you obtained in Task 5.3 and Task 5.5, based on the statistics from Task 5.1 and your calculation?

-----------------
SECTION 3. DELIVERABLES


You are required to turn in two files (use StudentID to name your files):

1. StudentID.pdf: (replacing StudentID) – Submit on Blackboard via the Turnitin link “Report Submission”
A report that answers all the questions in Section 2 including all the necessary SQL statements and screenshots of their outputs.

2. StudentID.sql: (replacing StudentID) – Submit on Blackboard via the standard upload link “SQL Script Submission”
A plaintext script file that includes all your SQL statements.

Your report file should include the following content:

• Answers to all the Questions in Section 2.

• If you are asked to write SQL statements, you need to include those statements in your report.



Enjoy the project! Good luck!