C175 Pre Assessment
What is an important aspect of "referential integrity"? 1. Primary keys refer to data in particular relation 2. Reference points are placed by the database in each record during backups 3. The relationships between entities and attributes are called referrals 4. Reference to data in one relation is based on values in another relation
reference to data in one relation is based on values in another relation
Where does affinity grouping occur in data mining? 1. Among entities and target applications 2. Between entity group names 3. Between objects 4. Among clusters
Between objects
A manager asks an employee to list attributes of the customers that are headquartered in Los Angeles and that have a customer number higher than 1000. Refer to the given SQL statement prepared by this employee. SELECT CUSTNUM, CUSTNAME, HQCITY FROM CUSTOMER WHERE HQCITY='Los Angeles' Which line should go at the end of this statement? 1. AND CUSTNUM>1000; 2. AND CUSTNUM>=1000; 3. WHERE CUSTNUM<1000 4. WHERE CUSTNUM>=1000;
AND CUSTNUM>1000;
What is a term for a set of columns in a table that can uniquely identify any record in that table without referring to other data? 1. Foreign key 2. Primary key 3. Alternate key 4. Candidate key
Candidate key
Which technology has no internal hierarchy? 1. Flat files 2. Heap files 3. Hashed tables 4. Relational Databases
Flat files
What is the term for the value of one particular attribute associated with a specific single value of another attribute? 1. Functional dependency 2. Transitive dependency 3. Decomposition 4. Normalization
Functional dependency
Why is an index created on a database column? 1. To optimize data integrity 2. To optimize data updates 3. To optimize data retrievals 4. To optimize data insertions
To optimize data retrievals
Why are indexes created in a physical database design? 1. To group data into aggregations 2. To iterate across data in a sequence 3. To retrieve data directly using a pointer 4. To summarize data into dimensions for a cube
To retrieve data directly using a pointer
During which step in the extract, transform, load (ETL) process are raw data sets aggregated? 1. Loading 2. Extraction 3. Conversion 4. Transformation 5. Denormalization
Transformation
Refer to the given SQL statement. SELECT SPNUM, SPNAME FROM SALESPERSON What is the correct line to add to the end of this statement to find salespersons with a commission percentage of 15? 1. * COMMPERCT=15; 2. IF COMMPERCT=15; 3. AND COMMPERCT=15; 4. WHERE COMMPERCT=15;
WHERE COMMPERCT=15;
What is necessary for a primary key in one relation of a database to match with its corresponding foreign key in another relation of the same database? 1. A domain of values 2. Intersection data 3. An attribute name 4. A quantity
A domain of values
Sales data, detailing the customer names, products sold, and salespersons, is kept in a database. Which kind of data in this database would qualify as intersection data related to both the product and salesperson entities? 1. Quantity 2. Products 3. Salespersons 4. Customer names
Customer names
What is a methodology for organizing attributes into tables? 1. Data normalization 2. Data redundancy 3. Data indexing 4. Data compression
Data normalization
What is the uniquely identifiable element about which data can be categorized in an entity-relationship diagram? 1. Entity types 2. Primary keys 3. Unary relationships 4. Intersection data points
Entity types
Which data classification is an entity? 1. Event 2. Duration 3. Directions 4. Attendance
Event
The given SQL statement is intended to query how many books there are with at least 800 pages from publishers in Los Angeles, United States. SELECT COUNT(*) ? WHERE PUBLISHER.PUBNAME=BOOK.PUBNAME AND CITY='Los Angeles' AND COUNTRY='United States' AND PAGES>=800; With which line should the question mark in this statement be replaced? 1. FROM PUBNAME.BOOK 2. FROM PUBLISHER, BOOK 3. WHERE PUBNAME = BOOK 4. WHERE PUBLISHER = BOOK
FROM PUBLISHER, BOOK
What are data? 1. Facts that have been organized in a meaningful way 2. Facts that are the result of a query of a database system 3. Facts that are collected and stored in a database system 4. Facts that have been processed and used for decision making
Facts that are collected and stored in a database system
A product marketing company publishes an Internet-based newsletter about their new products to increase their customer base. What is an advantage that this company will gain from investing in a relational database management system that will store customer information? 1. Increased sales 2. Lower advertising costs 3. Improved query response times 4. Decreased skill acquisition times
Improved query response times
Which set of results should a company expect from implementing a business intelligence system? 1. Increased profitability and increased throughput 2. Reduced hardware redundancy and decreased workloads 3. Increased profitability and reduced hardware redundancy 4. Riskier capital and asset investments and increased throughput
Increased profitability and increased throughput
Which three kinds of rules for referential integrity are provided by modern relational database management systems? (Choose 3 answers) 1. Sort 2. Insert 3. Query 4. Delete 5. Update 6. Retrieve
Insert Delete Update
What is a determining characteristic of unstructured data? 1. It does not allow copying and pasting. 2. It is easy to query and retrieve by business applications. 3. It does not follow a data model. 4. It is stored in rows and columns.
It does not follow a data model.
In which two ways does a database management system environment increase effectiveness in working with data? (Choose 2 answers) 1. It enables data sharing 2. It duplicates redundant data for security 3. It permits storage of vast volumes of data 4. It increases the complexity rules by which data is organized
It enables data sharing It permits storage of vast volumes of data
What happens to the original data in database indexing? 1. It is moved to the index 2. It is copied to the index 3. It is compiled by the DBMS 4. It is translated into hexadecimals
It is copied to the index
Refer to the given SQL statement to answer the following question: SELECT * FROM PRODUCT; What would this SQL statement accomplish? 1. List all PRODUCT from the * table. 2. Delete all products from the PRODUCT table view. 3. Delete all entries in the PRODUCT table. 4. List all entries in the PRODUCT table.
List all entries in the PRODUCT table.
A salesperson is authorized to sell 12 products; a product can be sold by 10 salespersons. Which kind of binary relationship is described in this example? 1. One-to-one 2. One-to-many 3. Many-to-many 4. Associative
Many-to-many
Which issue is focused on the loading component of extract, transform, load (ETL)? 1. Monitor refreshing volume and frequency 2. Denormalizing and renormalizing the data 3. Mapping keys from one system to another 4. Determining the content of the data
Monitor refreshing volume and frequency
Which SQL statement alphabetizes customer names within the same satellite-office city? 1. ORDER BY CUSTNAME, SATCITY; 2. ALPHA BY CUSTNAME, SATCITY; 3. ORDER BY SATCITY, CUSTNAME; 4. ALPHA BY SATCITY, CUSTNAME;
ORDER BY SATCITY, CUSTNAME;
What is a key difference between the DISTINCT and ORDER BY statements, in SQL SELECT commands? 1. ORDER BY does not alter the presentation of data results and DISTINCT modifies data results. 2. ORDER BY modifies the presentation of data results and DISTINCT filters data results. 3. ORDER BY changes the order of results in the database and DISTINCT changes the order of results in the view only. 4. ORDER BY changes the order of results in the view only and DISTINCT changes the order of results in the database.
ORDER BY modifies the presentation of data results and DISTINCT filters data results.
How is prediction distinguished from estimation in data mining? 1. Prediction is used to look at historical data only. 2. Estimation assumptions do not need to be tested. 3. Prediction classifies objects according to an expected future behavior. 4. Estimation divides small collections of entities into smaller groups of similar entities.
Prediction classifies objects according to an expected future behavior
What is an attribute or group of attributes that uniquely identify a tuple in a relation? 1. Index key 2. Foreign key 3. Primary key 4. Physical key
Primary key
What is a broad definition of data? 1. Numbers that are captured on digital media 2. Raw facts that are captured on printed or digital media 3. Alphanumeric combinations that can be captured on media that a computer can read 4. Any information that can be transferred from print to digital
Raw facts that are captured on printed or digital media
Refer to the given SQL statement. SELECT COMMPERCT, YEARHIRE FROM SALESPERSON WHERE SPNUM=22; How should this statement be altered to retrieve the entire record instead of the commission percentage and year of hire? 1. Replace WHERE SPNUM=22; with WHERE SPNUM=* 2. Replace COMMPERCT, YEARHIRE with an asterisk 3. Replace COMMPERCT, YEARHIRE with ALL 4. Replace SALESPERSON with ALL
Replace COMMPERCT, YEARHIRE with an asterisk
Which SQL statement will retrieve rows for all stores in Atlanta or Los Angeles or New York? 1. SELECT StoreID, City FROM Suppliers WHERE City IN ('Atlanta', 'Los Angeles', 'New York'); 2. SELECT StoreID, City FROM Suppliers WHERE City BETWEEN 'Atlanta' AND 'Los Angeles' AND 'New York'; 3. SELECT StoreID, City FROM Suppliers WHERE City BETWEEN 'Atlanta' OR 'Los Angeles' OR 'New York'; 4. SELECT StoreID, City FROM Suppliers WHERE (City='Atlanta' AND City='Los Angeles' AND City='New York');
SELECT StoreID, City FROM Suppliers WHERE City IN ('Atlanta', 'Los Angeles', 'New York');
How were data retrieved before database management systems? 1. Randomly from linked files 2. Sequentially from simple files 3. Using set operations on complex files 4. Using relationships between logical entities
Sequentially from simple files
What uniquely identifies each entity in a collection of entities but is not the primary key? 1. The foreign key 2. The secondary key 3. The alternate key 4. The master key
The alternate key
What is true about flat files? 1. They contain no internal hierarchical organization 2. They have a limit of 256 records. 3. They can only contain two-dimensional data. 4. They are always encrypted
They contain no internal hierarchical organization
The given SQL statement is intended to list the names of the products of which salesperson Fox has sold more than 500 units. SELECT PRODNAME FROM SALESPERSON, SALES, PRODUCT ? ? AND SPNAME='Fox' AND QUANTITY>500; Which set of lines should replace the question marks to make this statement work? 1. WHERE SALESPERSON.SPNUM=PRODUCT.PRODNUM AND SALES.PRODNUM=PRODUCT.PRODNUM 2. WHERE SALESPERSON.SPNUM=SALES.SPNUM AND SALES.PRODNUM=PRODUCT.PRODNUM 3. WHERE SALESPERSON.SPNUM>SALES.SPNUM AND SALES.PRODNUM=PRODUCT.PRODNUM 4. WHERE SALESPERSON.SPNUM=SALES.SPNUM AND SALES.PRODNUM=SALES.SPNUM
WHERE SALESPERSON.SPNUM=SALES.SPNUM AND SALES.PRODNUM=PRODUCT.PRODNUM