Podcast
Questions and Answers
What does DBMS stand for?
What does DBMS stand for?
Database Management System
What is the definition of data integrity?
What is the definition of data integrity?
Data integrity refers to the consistency of data in a database, ensuring adherence to defined rules to maintain accuracy and reliability.
Which of the following is NOT a potential advantage of using a database?
Which of the following is NOT a potential advantage of using a database?
- Lower Cost (correct)
- Improved Data Consistency
- Enhanced Data Accessibility
- Increased Data Security
What is a backup in the context of databases?
What is a backup in the context of databases?
What does the term "concurrent" refer to in database management?
What does the term "concurrent" refer to in database management?
What is meant by "data security" in database management?
What is meant by "data security" in database management?
In a database system, what is a query?
In a database system, what is a query?
Who are naive users in the context of database management?
Who are naive users in the context of database management?
It is typically the responsibility of the database administrator to write commands for creating a database structure.
It is typically the responsibility of the database administrator to write commands for creating a database structure.
What is data consistency?
What is data consistency?
Which level of the three-level database architecture contains user views?
Which level of the three-level database architecture contains user views?
What is Data Manipulation Language (DML)?
What is Data Manipulation Language (DML)?
What are the two essential parts of a data sublanguage?
What are the two essential parts of a data sublanguage?
Give an example of data rather than information.
Give an example of data rather than information.
On the logical level of the database, what is metadata?
On the logical level of the database, what is metadata?
Which of the following can be an entity?
Which of the following can be an entity?
Which of the following can be an attribute?
Which of the following can be an attribute?
In an ER diagram, what participation constraint is indicated by a single line between an entity set rectangle and a relationship diamond?
In an ER diagram, what participation constraint is indicated by a single line between an entity set rectangle and a relationship diamond?
No two attributes in a relationship can share a domain.
No two attributes in a relationship can share a domain.
In the ER model, what symbol is used to represent an attribute that can have multiple values for an entity instance?
In the ER model, what symbol is used to represent an attribute that can have multiple values for an entity instance?
A primary key can consist of more than one attribute.
A primary key can consist of more than one attribute.
The basic objects in the ER model include all of the following EXCEPT:
The basic objects in the ER model include all of the following EXCEPT:
In the ER model, a dashed oval is used to indicate which kind of attribute?
In the ER model, a dashed oval is used to indicate which kind of attribute?
A relationship set cannot have attributes of its own.
A relationship set cannot have attributes of its own.
Which data model level does an ER diagram best describe?
Which data model level does an ER diagram best describe?
On an ER diagram, how is the primary key of an entity indicated?
On an ER diagram, how is the primary key of an entity indicated?
In the ER model, what is a composite attribute?
In the ER model, what is a composite attribute?
What is a superkey in the context of the ER model?
What is a superkey in the context of the ER model?
In the ER model, what is a binary relationship?
In the ER model, what is a binary relationship?
What type of model is the ER model classified as?
What type of model is the ER model classified as?
In the ER model, what is the set of values permitted for an attribute called?
In the ER model, what is the set of values permitted for an attribute called?
In a bank, if savings accounts can be jointly owned by multiple customers, and customers can have multiple savings accounts, what type of relationship exists between the SavingsAccounts entity set and the Customer entity set?
In a bank, if savings accounts can be jointly owned by multiple customers, and customers can have multiple savings accounts, what type of relationship exists between the SavingsAccounts entity set and the Customer entity set?
In a university, students can get at most one parking permit for one car. Not all students have cars, and no car is allowed on campus without a permit. What is the participation constraint for the "Car" entity in the relationship to the "Student" entity?
In a university, students can get at most one parking permit for one car. Not all students have cars, and no car is allowed on campus without a permit. What is the participation constraint for the "Car" entity in the relationship to the "Student" entity?
In a business, if a department can have many workers, but each worker belongs to only one department, what is the cardinality of the department-to-worker relationship?
In a business, if a department can have many workers, but each worker belongs to only one department, what is the cardinality of the department-to-worker relationship?
In the ER model, what does cardinality refer to?
In the ER model, what does cardinality refer to?
A relationship in an ER diagram always connects two entity sets.
A relationship in an ER diagram always connects two entity sets.
In the relational model, the number of columns in a table corresponds to which property of a relation?
In the relational model, the number of columns in a table corresponds to which property of a relation?
What is referential integrity in the relational model?
What is referential integrity in the relational model?
If A and B are entity sets with a one-to-one relationship, which of the following is NOT true of the relational model representation?
If A and B are entity sets with a one-to-one relationship, which of the following is NOT true of the relational model representation?
In mapping a relationship to a relational schema, which of the following always requires a separate table?
In mapping a relationship to a relational schema, which of the following always requires a separate table?
Which of the following types of attributes can be directly represented as a column in a relational model?
Which of the following types of attributes can be directly represented as a column in a relational model?
What is a foreign key in the relational model?
What is a foreign key in the relational model?
In converting from an ER diagram to a relational model, what do tables represent?
In converting from an ER diagram to a relational model, what do tables represent?
What property must a superkey have to be a candidate key?
What property must a superkey have to be a candidate key?
If S = {a,b} and T = {1,2,3}, then how many ordered pairs are in the Cartesian product S × T?
If S = {a,b} and T = {1,2,3}, then how many ordered pairs are in the Cartesian product S × T?
The attributes of a relation are represented in a table by what?
The attributes of a relation are represented in a table by what?
In the relational model, what does referential integrity place restrictions on?
In the relational model, what does referential integrity place restrictions on?
What is the customary way to indicate a primary key in a relation schema?
What is the customary way to indicate a primary key in a relation schema?
What is the entity integrity constraint in the relational model?
What is the entity integrity constraint in the relational model?
In the relational model, what is the relation schema?
In the relational model, what is the relation schema?
The degree of a relation is a characteristic of the intention of the relation.
The degree of a relation is a characteristic of the intention of the relation.
Every relation in a relational database schema must have a foreign key.
Every relation in a relational database schema must have a foreign key.
If S = {a,b} and T = {1,2,3}, which of the following can be a relation for S × T?
If S = {a,b} and T = {1,2,3}, which of the following can be a relation for S × T?
All of the following are characteristics of relations in the relational model EXCEPT:
All of the following are characteristics of relations in the relational model EXCEPT:
All of the following are examples of constraints on relations in the relational model EXCEPT:
All of the following are examples of constraints on relations in the relational model EXCEPT:
What is the best method for representing a weak entity in a relational schema?
What is the best method for representing a weak entity in a relational schema?
The SQL option HAVING can only be used with which other option?
The SQL option HAVING can only be used with which other option?
To eliminate duplicates in the results of an SQL query, use which option?
To eliminate duplicates in the results of an SQL query, use which option?
What is the proper way to create an alias, E, for relational table EMPLOYEE and retrieve all employee data?
What is the proper way to create an alias, E, for relational table EMPLOYEE and retrieve all employee data?
Which SQL function returns the number of values in a column?
Which SQL function returns the number of values in a column?
If NAME contains character string data, what SQL SELECT specification should be used with WHERE NAME LIKE ___________ to retrieve only records where NAME begins with M and ends with 'ton'?
If NAME contains character string data, what SQL SELECT specification should be used with WHERE NAME LIKE ___________ to retrieve only records where NAME begins with M and ends with 'ton'?
To display data retrieved using an SQL SELECT in ascending order, use which option?
To display data retrieved using an SQL SELECT in ascending order, use which option?
All of the following are SQL DDL commands EXCEPT:
All of the following are SQL DDL commands EXCEPT:
Which SQL predicate is used to find rows in the Employee table that have no value for rating?
Which SQL predicate is used to find rows in the Employee table that have no value for rating?
What specification in the SQL CREATE TABLE command enforces referential integrity?
What specification in the SQL CREATE TABLE command enforces referential integrity?
To retrieve all columns from table A in a SQL SELECT operation, what should the SELECT read?
To retrieve all columns from table A in a SQL SELECT operation, what should the SELECT read?
To delete all records from a table EMPLOYEE and destroy its structure, which command should be used?
To delete all records from a table EMPLOYEE and destroy its structure, which command should be used?
To insert a record into a table with an always IDENTITY column, should the column be included in the set of values for attributes?
To insert a record into a table with an always IDENTITY column, should the column be included in the set of values for attributes?
Given an Employee table with columns for salary and dept, how would you raise the salaries of all employees in the sales department by 10%?
Given an Employee table with columns for salary and dept, how would you raise the salaries of all employees in the sales department by 10%?
All relational database management systems support all features of the SQL standard.
All relational database management systems support all features of the SQL standard.
Flashcards
DBMS
DBMS
Software managing the database.
Data Integrity
Data Integrity
Rules ensuring database consistency.
Backup
Backup
A copy of the database for recovery.
Concurrent Access
Concurrent Access
Signup and view all the flashcards
Data Security
Data Security
Signup and view all the flashcards
Query (in a Database)
Query (in a Database)
Signup and view all the flashcards
Naive User
Naive User
Signup and view all the flashcards
Data Consistency
Data Consistency
Signup and view all the flashcards
External Level (Database Architecture)
External Level (Database Architecture)
Signup and view all the flashcards
Data Manipulation Language (DML)
Data Manipulation Language (DML)
Signup and view all the flashcards
Data Definition Language (DDL)
Data Definition Language (DDL)
Signup and view all the flashcards
Data vs. Information
Data vs. Information
Signup and view all the flashcards
DBA
DBA
Signup and view all the flashcards
Metadata
Metadata
Signup and view all the flashcards
Entity
Entity
Signup and view all the flashcards
Attribute
Attribute
Signup and view all the flashcards
Partial Participation
Partial Participation
Signup and view all the flashcards
Superkey
Superkey
Signup and view all the flashcards
Composite Attribute
Composite Attribute
Signup and view all the flashcards
Derived Attribute
Derived Attribute
Signup and view all the flashcards
Binary Relationship
Binary Relationship
Signup and view all the flashcards
Cardinality
Cardinality
Signup and view all the flashcards
Degree (of a Relation)
Degree (of a Relation)
Signup and view all the flashcards
Referential Integrity
Referential Integrity
Signup and view all the flashcards
Foreign Key
Foreign Key
Signup and view all the flashcards
Candidate Key
Candidate Key
Signup and view all the flashcards
Entity Integrity
Entity Integrity
Signup and view all the flashcards
Schema (Relational Model)
Schema (Relational Model)
Signup and view all the flashcards
SQL HAVING Clause
SQL HAVING Clause
Signup and view all the flashcards
SQL DISTINCT Clause
SQL DISTINCT Clause
Signup and view all the flashcards
SQL ORDER BY Clause
SQL ORDER BY Clause
Signup and view all the flashcards
SQL IDENTITY Column
SQL IDENTITY Column
Signup and view all the flashcards
SQL UPDATE Command
SQL UPDATE Command
Signup and view all the flashcards
Study Notes
Database Management Systems (DBMS)
- DBMS is the software that manages a database.
- Data Integrity is the consistency rules a database must follow.
- A Backup is a copy of the database for disaster recovery.
- Concurrent access means multiple users can access the database simultaneously.
- Data Security protects the database from unauthorized access.
- A Query is a question posed to the database (e.g., "Find students in ENG210").
- Naive Users interact with the database through application programs.
- The Database Administrator (DBA) writes commands to create database structure.
- Data Consistency means all copies of the same data item agree.
- The External level in the database architecture contains user views.
- Data Manipulation Language (DML) retrieves data from a database.
- Data Definition Language (DDL) and Data Manipulation Language (DML) are the core parts of a data sublanguage.
- An unordered list of grades is data, not information.
- Metadata is data about data (at the logical level).
- An entity can be a vendor.
- StudentID can be an attribute.
- Partial participation in an ER diagram is indicated by a single line between entities and relationship.
- Two attributes in a relationship cannot share the same domain.
- A double oval in an ER model represents an attribute with multiple values for an entity.
- A primary key can have multiple attributes.
- Classes are not basic objects in the ER Model.
- A dashed oval in the ER model shows a derived attribute.
- A relationship can have its own attributes.
- The ER diagram describes the conceptual data model.
- A primary key in an ER diagram is underlined.
- A composite attribute is an attribute divided into smaller parts (e.g., address).
- A superkey uniquely identifies an entity instance.
- A binary relationship links two entity sets.
- The ER model is a semantic model.
- The domain is the set of valid values for an attribute.
- The relationship between Savings Accounts and Customers is many-to-many.
Relational Databases
- Entity Integrity: A primary key cannot contain null values.
- Referential Integrity: A foreign key must match a primary key or be null.
- A many-to-many relationship requires a separate table when mapping to relations (SQL).
- A single-valued, non-composite attribute maps directly to a relation column.
- A foreign key references a primary key in another table.
- Tables represent both entities and relationships when converting from ER diagrams.
- A candidate key is a superkey with no proper subset that is also a superkey.
- Cartesian product size calculation (example given using S={a, b} and T={1, 2, 3}).
- A relation's attributes are represented as columns in a table.
- Foreign keys are constrained by referential integrity.
- An SQL primary key is indicated by underlining.
- The schema is the structure of a relation, including attributes and domain information.
- Relation degree is the number of columns in a table, not a characteristic of the relation's intent.
- Relations do not always have foreign keys.
- A relation for a Cartesian product example is given (S×T).
- A relation's cells contain only one value.
- Boundary constraints are not constraints on relations.
- Represent a weak entity by creating tables for both the strong and weak entities, including the strong entity's primary key in the weak entity's table.
- HAVING can only be used with GROUP BY.
- DISTINCT removes duplicates in SQL queries.
SELECT * FROM EMPLOYEE E;aliases EMPLOYEE as E and retrieves all its data.COUNTreturns the number of values in a column in SQL.'M%ton'retrieves names beginning with M and ending with 'ton' in SQL.ORDER BYsorts data in SQL.
SQL Commands
- SQL DDL commands are not ADD TABLE.
WHERE RATING IS NULLretrieves rows with null ratings.- The
FOREIGN KEYclause enforces referential integrity. SELECT * FROM A...retrieves all columns from table A.DROP EMPLOYEE;deletes a table (and all its data).WHERE RATING IS NULLfinds rows with null 'rating' values.- Always IDENTITY columns in SQL should not include columns in the set of values.
- The SQL command
UPDATE Employee SET salary = salary*1.10 WHERE dept='sales';raises sales department salaries by 10%. - Not all relational database systems support all SQL standard features.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on Database Management Systems (DBMS) with this quiz. Explore concepts such as data integrity, security, and the roles of database administrators. Perfect for anyone looking to solidify their understanding of database fundamentals.
