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The correct option is (a) A diamond

Explanation: When a single PARENT-child RELATIONSHIP exists, the relationship is called binary. All of the previous examples of relationships to this point have been binary relationships. However, when creating a DATA model, it is not uncommon to come across n-array relationships, the MODELING name for relationships between two or more parent entities and a single child table.

The correct answer is (b) Records

Easy explanation: In the context of a RELATIONAL database, a row also CALLED a record or tuple represents a single, IMPLICITLY STRUCTURED data item in a table.

Right option is (c) small open diamond at the end of a line connecting two tables

Easy explanation: There are THREE primary inter-object relationships: ASSOCIATION, aggregation, and composition. Using the right relationship line is important for placing implicit restrictions on the visibility and propagation of changes to the related classes, matter which PLAY major role in REDUCING system complexity.

Right answer is (d) All of the Mentioned

The best explanation: To DESIGNING database from the POINT of USER view we need all the mentioned REQUIRED.

The CORRECT answer is (a) Network MODEL

Explanation: The network model is a database model conceived as a FLEXIBLE WAY of representing objects and their relationships.

The CORRECT OPTION is (c) DOUBLY outlined rectangle

Explanation: A weak ENTITY set is indicated by a doubly-outlined BOX.

The CORRECT OPTION is (C) A tuple

Explanation: A tuple is analogous to a record in non-relational databases.

The CORRECT answer is (a) Rectangle

Easy EXPLANATION: Entity types REPRESENT sets of objects and are pictured by RECTANGULAR NODES.

The correct choice is (c) A data element/attribute within a data FIELD of a data record within a database table that is a PRIMARY key in another database table

The BEST I can explain: A FOREIGN KEY CONSTRAINT can reference columns in tables in the same database or within the same table. These are called self-referencing tables. For example, consider an employee table that contains three columns: employee_number, employee_name, and manager_employee_number. Because the manager is also an employee, there is a foreign key RELATIONSHIP from the manager_employee_number column to the employee_number column.

Correct answer is (a) Parent child relationship between the tables that connect them

To explain I would SAY: In a FOREIGN key reference, a link is created between two tables when the column or columns that hold the primary key VALUE for one table are referenced by the column or columns in ANOTHER table. This column becomes a foreign key in the second table.

Correct choice is (b) Specifying a zero (0) for the LOWER bound for the association multiplicity on a class diagram INDICATES that the item is required

Easy EXPLANATION: A foreign key is a column that references a column (most often the primary key) of another table. The purpose of the foreign key is to ensure referential integrity of the data. In other WORDS, only values that are supposed to appear in the database are permitted.

Correct answer is (b) Candidate key

For explanation: A candidate key is a combination of attributes that can be uniquely used to IDENTIFY a database RECORD without any extraneous data. Each table may have one or more candidate KEYS. One of these candidate keys is selected as the table PRIMARY key.

Correct choice is (a) FOREIGN Key

Easy EXPLANATION: A foreign key is a key USED to link two TABLES together. This is sometimes called a REFERENCING key.Foreign Key is a column or a combination of columns whose values match a Primary Key in a different table.

The CORRECT ANSWER is (C) Primary Key

Best explanation: Primary Key by default it ADDS a clustered index.

Right OPTION is (b) UNIQUE can have single NULL value but Primary can’t have even single.

To EXPLAIN I would SAY: Primary key doesn’t allow Null values and Unique key allows Null value, but only ONE Null value.

Right option is (d) Secondary

The best I can explain: Except Secondary all are the TYPES of KEY in SQL SERVER.

Right CHOICE is (C) CANDIDATE

The explanation: In the relational model of databases, a candidate key of a relation is a MINIMAL SUPERKEY for that relation.

Right answer is (d) All of the MENTIONED

Easiest EXPLANATION: Adding KEY on a table can be DONE with all the above mentioned way.

Right answer is (c) Referential INTEGRITY Constraint

For EXPLANATION I WOULD SAY: Referential Integrity is set of constraints applied to foreign key which prevents ENTERING a row in child table for which you don’t have any corresponding row in parent table i.e. entering NULL or invalid foreign keys.

The correct choice is (a) A -> B

To explain I WOULD say: TRANSITIVITY rule: Same as transitive rule in ALGEBRA, if a -> b HOLDS and b -> C holds then a -> c also hold. a -> b is called as a functionally determines b.

The correct answer is (a) Candidate

The explanation is: A candidate key is a column, or SET of columns, in a table that can uniquely identify any DATABASE record without referring to any other data. Each table MAY have ONE or more candidate KEYS.

Right option is (B) Decomposition

To elaborate: ELIMINATE REDUNDANCY by decomposing a relation into several relations in a HIGHER normal form.

The correct choice is (d) Transitive DEPENDENCIES

To explain I would say: Third Normal Form DEALS with something called ‘transitive’ dependencies. This MEANS if we have a primary key A and a non-key domain B and C where C is more dependent on B than A and B is directly dependent on A, then C can be considered transitively dependent on A.

Correct CHOICE is (c) Domain/key normal form

The EXPLANATION is: A relation is in domain-key normal form (DK/NF) if every CONSTRAINT on the relation is a LOGICAL CONSEQUENCE of the definition of keys and domains.

Correct option is (B) Transitive Dependencies

Easy explanation: For a relation to be in Third Normal Form, it MUST be in Second Normal form and the following must SATISFY:No non-prime attribute is TRANSITIVELY dependent on prime key attribute For any non-trivial functional DEPENDENCY, X -> A, then eitherX is a superkey or,A is prime attribute.

Correct choice is (a) REDUCED training COSTS

Easiest explanation: Standard RELATIONAL language GIVES the benefits of reducing the training costs.

Correct answer is (d) ONE row has the value “He is interested in a SILVER Porsche from the years 1978-1988” in a COLUMN

The best EXPLANATION: Option d fullfill the condition of column.

Correct CHOICE is (B) An exact match is not possible in a SELECT STATEMENT

Easy explanation: Wildcard USEFUL only when an exact match is not possible in a SELECT statement.

Correct choice is (B) Pull

For EXPLANATION: The push-pull MODEL to not allow mixed port type combinations for a connection, such as connecting a push OUTPUT port to a pull INPUT port, and a pull output port to a push input port.

Right option is (c) Too much data

For EXPLANATION: The curse of dimensionality refers to various phenomena that ARISE when ANALYZING and organizing data in high-dimensional spaces.

Correct choice is (c) Modify data

Easy explanation: BUSINESS intelligence (BI) is a technology-driven PROCESS for filter data and group information.

The correct choice is (c) USE statistical PROCEDURES to predict future events

Explanation: Business intelligence (BI) is a technology-driven process for analyzing data and PRESENTING ACTIONABLE INFORMATION.

Right choice is (d) Enabler

The EXPLANATION is: The CREATE ASSERTION statement names a NEW CONSTRAINT and defines the Constraint’s deferral mode, initial constraint CHECK time and its CHECK search condition.

Right answer is (a) An INSTANCE of a SUBTYPE participates in a relationship that is unique to that subtype

The explanation: Super-types and sub-types show HIERARCHY in the structure; graphs and TREES show hierarchy in the data.

Right ANSWER is (c) Each subtype has only one supertype

Easy explanation: Two ENTITIES are of DISTINCT types if they have no attributes in common. It is POSSIBLE for entities to have both common and distinct attributes. If they have a common identifier (that is, a common primary KEY), they have a special supertype-subtype relationship: they are neither distinct nor the same.

The correct option is (a) Disjoint with TOTAL specialization

The explanation is: GradStudent (_id_, NAME, gradStuff) UndergradStudent (_id_, name, underGradStuff) Professor (_id_, name) TEACHES(_prof_id_, _stud_id_)

Considering that the relational database above is meant to represent total disjoint specialization, i.e. there is no table Student but rather two completely separate ones, when writing this in SQL in ORDER to implement the database, how would I fetch the student id for the Teaches table? I cannot figure out how to MAKE a foreign key from two different tables.

Right OPTION is (b) Physical DATABASE design

Easiest explanation: Physical database design is the PROCESS of SELECTING the data storage and data access characteristics of the database.

Correct CHOICE is (b) Inconsistent state

The best explanation: If the state of the database no LONGER REFLECTS a real state of the world that the database is SUPPOSED to capture, then such a state is calledin CONSISTENT state.

The correct ANSWER is (b) you need to UNDERSTAND the model the RECORD management system uses

The best EXPLANATION: For get to know the RMS (Record Management System) you should know the FLOW and of model and record management system.

The correct CHOICE is (c) It may include restrictions.

For explanation I WOULD say: According to the business rule it ALWAYS may include restrictions.