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WorksheetsCh3_Relational Data Model
Total questions: 15
Worksheet time: 8mins
Define Normalization
Process for restructuring tables into single table containing all information needed
Process representing data relationship in the form of a table that consist of row and column
Process for retrieving information from relational database using suitable operators
Process for assigning attributes to entities to determine whether the chosen entities, attributes and primary keys are appropriate and suitable for the system
The following are purpose of normalization in database model EXCEPT:
Minimize data redundancy
Allows database to be expanded if new requirements needed
Reduce security problems in database by concurrency control
Ensure good database schema which is represented by accurate table structure
Identify the importance of normalization in database.
To create relational tables
To maintain anomalies and accuracy
To reduce integrity and consistency of the data
To minimize redundancy and eliminate anomalies
The following are types of anomalies EXCEPT …
Insertion anomalies
Deletion anomalies
Duplication anomalies
Modification anomalies
Identify the characteristic that the table is in First Normal Form (1NF).
The primary key is defined in all tables
Rows has different values from each other
The table contains one or more repeating groups
Each attribute contains one and only one atomic value
Functional dependency (FD) can be denoted as A --> B. Choose the CORRECT definition of FD.
For any relation R, B is functionally dependent on A, if each value of A is associated with exactly one value of B
For any relation R, A is functionally dependent on B, if each value of A is associated with exactly one value of B
For any relation R, B is functionally dependent on A, if each value of A is associated with all value of B
For any relation R, A is functionally dependent on B, if each value of A is associated with all value of B
The relational tables are in Second Normal Form if all the following are removed:
Transitive dependency
Functional dependency
Full functional dependency
Partial functional dependency
Referring to the given relational schema, chose the attributes that violate the second normal form (2NF) property.
Supplier (SupID, SupName, Phone, Address, productName)
SupID
SupName
Address
ProductName
Choose the type of entity that only exist in the database while it is dependent to another entity in the same database.
Strong entity
Weak entity
Simple entitiy
Derived entity
Choose the basic elements of Entity Relationship Diagram (ERD).
Attributes, Relationship, Primary Key
Attributes, Entity, Primary Key
Attributes, Relationship, Entity
Attributes, Records, Entity
Select the CORRECT symbol for entity in E-R Diagram.
Oval
Square
Diamond
Rectangle
Choose the symbol used to represent relationship in Chen Notation.
Oval
Square
Diamond
Rectangle
Identify the relationship shown in Figure 1.
One to One
One to Many
Many to None
Many to Many
Select the CORRECT relationship based on the given situation in the statement :
“Each student is assigned to an academic advisor. Each academic advisor has multiple students under their supervision”
1 : 1
1 : M
M : M
M : N
Identify the relationship cardinality symbol shown in Figure 2.
One
Zero or many
Zero
One or many
