15- Consider the following Entitiy Relationship diagram. Which of the following relation will not hold if the above ER diagram is mapped into a relational model? I) Product (Productld, Desciption) II) Requests (Productld, Orderld) III) Order (Orderld, Productid, Date) IV) Order (Orderld, Date) ProductID Description Orderld Date M N Product Requests Order IV b) O I a) II II Leave blank Close c)

15- Consider the following Entitiy Relationship diagram. Which of the following relation will not hold if the above ER diagram is mapped into a relational model? I) Product (Productld, Desciption) II) Requests (Productld, Orderld) III) Order (Orderld, Productid, Date) IV) Order (Orderld, Date) ProductID Description Orderld Date M N Product Requests Order IV b) O I a) II II Leave blank Close c)

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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In SQL, foreign key constraints can reference only the primary key attributes ofthe referenced relation or other attributes declared to be a superkey using theunique constraint. As a result, total participation constraints on a many-to-manyrelationship set (or on the “one” side of a one-to-many relationship set) cannotbe enforced on the relations created from the relationship set, using primarykey, foreign key, and not null constraints on the relations. Explain why
PLZ help with the following: Translate your ER diagram into a relational schema in the form of SQL DDLs. Choose appropriate data types for each attribute and include primary key and foreign key constraints, Check and Not Null constraints. Normalize the relations to 3NF.
Develop an Entity Relationships Diagram (ERD) based on the relational schemas in the 3NF for the starting relational schema in un-normalized form presented below. UNF:Order(OrderID, OrderDate, CustID, CustName, CustPhone, CCNum, CCExpDate, CCBank, BnkContName, BnkContPhone, CustEmail, OrderIP, SiteRefFrom, ShipStreet, ShipCity, ShipSt, ShipZip, OrderLineNum, ItemID, ItemName, ItemDesc, ItemQtyOrdered,ItemListPrice, ItemSalePrice, ItemQtyShip, ShipCharge, Tax, TotalDue)
For developing our queries, we will be using the following relational schema: Student(SID, name, username, major) Course(cname, description, department, weight) Offering(OID, cname, year, term, duration) Enrolled(SID, OID, grade) A course relation is the generic description of a course which is offered by a department. The offering relation is the specific instance of a course being taught in a given term, and is the entity which will be associated with the student enrollment. Students are enrolled in these offerings and achieve a mark. Express each of following queries in Relational Algebra: | Write a relational algebra query which will list the cname and description of all the courses which are being offering in the Fall 2018 term. 2 Write a relational algebra query which will list the name of all the students who have earned 60% in both 'COSC2P12' and 'COSC2P13'.
In SQL, foreign key constraints can reference only the primary key attributes ofthe referenced relation or other attributes declared to be a superkey using theunique constraint. As a result, total participation constraints on a many-to-manyrelationship set (or on the “one” side of a one-to-many relationship set) cannotbe enforced on the relations created from the relationship set, using primarykey, foreign key, and not null constraints on the relations. Explain how to enforce total participation constraints using complexcheck constraints or assertions (see Section 4.4.8). (Unfortunately, thesefeatures are not supported on any widely used database currently.)
What are three advantages of using a surrogate key rather than the main key to access a relation instead?
Convert the Entity Relationship Diagram in to relational database by using MS Access (Note: Students has to create tables in the MS Access by giving appropriate Primary key and Foreign key relationships) QI. Customer Order OrderDetail CustomeriD OrderiD OrderiD (FK) OrderDetaillD Name Mail ZipCode Address Telephone CustomeriD (FK) OrderDate TotalPrice ProductiD (FK) Amount Price Product ProductiD Name Kind Price
Create an unnormalized relation using student and class entities.
Implement a new independent entity phone in the Sakila database. Attributes and relationships are shown in the following diagram: The diagram uses Sakila naming conventions. Follow the Sakila conventions for your table and column names: All lower case Underscore separator between root and suffix Foreign keys have the same name as referenced primary key Write CREATE TABLE and ALTER TABLE statements that: Implement the entity as a new phone table. Implement the has relationships as foreign keys in the Sakila customer, staff, and store tables. Remove the existing phone column from the Sakila address table. Step 2 requires adding a foreign key constraint to an existing table. Ex: ALTER TABLE customer ADD FOREIGN KEY (phone_id) REFERENCES phone(phone_id) ON DELETE SET NULL ON UPDATE CASCADE; Specify data types as follows: phone_id, phone_number, and country_code have data type INT. phone_type has date type VARCHAR(12) and contains strings like 'Home', 'Mobile', and 'Other'. Apply…
Implement a new independent entity phone in the Sakila database. Attributes and relationships are shown in the following diagram: The diagram uses Sakila naming conventions. Follow the Sakila conventions for your table and column names: All lower case Underscore separator between root and suffix Foreign keys have the same name as referenced primary key Write CREATE TABLE and ALTER TABLE statements that: Implement the entity as a new phone table. Implement the has relationships as foreign keys in the Sakila customer, staff, and store tables. Remove the existing phone column from the Sakila address table. Step 2 requires adding a foreign key constraint to an existing table. Ex: ALTER TABLE customer ADD FOREIGN KEY (phone_id) REFERENCES phone(phone_id) ON DELETE SET NULL ON UPDATE CASCADE; Specify data types as follows: phone_id, phone_number, and country_code have data type INT. phone_type has date type VARCHAR(12) and contains strings like 'Home', 'Mobile', and 'Other'. Apply…
Implement a new independent entity phone in the Sakila database. Attributes and relationships are shown in the following diagram: The diagram uses Sakila naming conventions. Follow the Sakila conventions for your table and column names: All lower case Underscore separator between root and suffix Foreign keys have the same name as referenced primary key Write CREATE TABLE and ALTER TABLE statements that: Implement the entity as a new phone table. Implement the has relationships as foreign keys in the Sakila customer, staff, and store tables. Remove the existing phone column from the Sakila address table. Step 2 requires adding a foreign key constraint to an existing table. Ex: ALTER TABLE customer ADD FOREIGN KEY (phone_id) REFERENCES phone(phone_id) ON DELETE SET NULL ON UPDATE CASCADE; Specify data types as follows: phone_id, phone_number, and country_code have data type INT. phone_type has date type VARCHAR(12) and contains strings like 'Home', 'Mobile', and 'Other'. Apply…
Instructions: Create a complete ERD in Crow's Foot notation that can be implemented in the relational model using the descriptions below. The attributes required: Activity's ID, Activity's Title, Activity's description, Child's ID, Child's firstname and lastname, Child's Birthday, Parent's ID, Parent's number, Parent's address. The business rules are: An activity may or may not have a child signed up An activity may have many children signed up A child must have an activity A child may have many activities A child must have a parent A parent must have a child A child may have many parents A parent may have many children To submit: Write your answer in a clean sheet of paper and upload a picture of it to dropbox