
Concept explainers
A.
Explanation of Solution
“Yes”, SQL server supports both locking such as optimistic and pessimistic.
Reason:
The SQL server supports the optimistic and pessimistic locks.
Optimistic lock:
- Multiple users can update the data and it gets lock after the transaction has been processed in optimistic lock. It can be used for web applications.
- There is no conflict occur during transaction. If conflict occurs then it can be repeated until no conflict.
- There is no need to lock the
database resources and it prevents database from deadlocks. - The disadvantage is that it allows the applications from selecting and modifying the same data...
B.
Explanation of Solution
Transaction Isolation Level:
The transaction isolation level gives the measure of the extent to which transaction isolation succeeds.
- This process is defined by the presence or the absence of the phenomena such as dirty read, nonrepeatable reads, and phantom read.
- These problems occur when we read data from the database.
There are four levels of transactions. They are,
- Read uncommitted isolation level
- Read committed isolation level
- Repeatable reads isolation level
- Serializable isolation level
Read uncommitted isolation level:
Read uncommitted isolation level is the lowest isolation level which allows dirty reads, nonrepeatable reads, and phantom reads.
- It makes the transaction to read any data currently on a data page irrespective of the data has been committed.
- The uncommitted read isolation level applies to read-only operations like SELECT, SELECT INTO, and FETCH.
- The uncommitted read should not be applied for the cases where the answer must be accurate.
- The uncommitted read does affect other transactions.
Read committed Isolation level:
Read committed Isolation level allows nonrepeatable reads and phantom reads but it prevents dirty read...
C.
Explanation of Solution
Cursor:
The term cursor is used to retrieve the information in row by row manner. If the records stored in the database table, which needs to be updated one row at a time is carried over by cursor.
- It plays the major role for fetching a required row from the table in the database which holds numerous records.
- Cursors are defined using SELECT statement.
- It points the set of rows which is resulted from an SQL SELECT statement.
- In general the cursor is placed in the first or last row.
- It influences the performance of the SQL Server as it uses the SQL server instances memory, decrease network bandwidth, and reduction in concurrency.
- It’s recommended to avoid the use of cursor and the cursor can be replaced with WHILE loop, temporary tables, and sub queries.
- The types of cursor are listed below:
- Forward-only cursor
- Static cursor
- Dynamic cursor
- Keyset cursor
Forward-only cursor:
Forward-only cursor is used for fastest retrieval of data from the database. It is the fastest cursor among all the cursors but with the drawback it does not support backward scrolling.
- Data deletion, updating the data can be done using the Forward-Only cursor.
- It is sensitive as any changes made in the database will affect the original data source...
D.
Explanation of Solution
Difference between Security model for SQL server and figure 6-16:
Note: Refer Figure 6-16 in textbook: “A model of DBMS security”
Security model for SQL server | Security model for database Management system |
It provides the security architecture to permit the database developer to make secure database application and counter threats. |
It provides the |
It contains the hierarchical set of entities with server. Each and every server contains multiple databases, and each and every database contains set of securable objects... |
E.
Explanation of Solution
Types of SQL server backup:
There are different types of SQL server backups. They are,
- Full backup
- Differential backup
- Transaction log backup
- Database file and Filegroup backups
Full backup:
The full backup in SQL server is simple type of backup which does not depends on recovery model.
- It backs up the any type of activity during the backup.
- It backs up any type of uncommitted transactions in transaction log file.
Differential backup:
The differential backup helps to reduce the time for restoring the modified database.
- It backs up the portion of database that have modified since final full database backup.
- It backs up any type of activity during differential backup and also any type of uncommitted transactions in transaction log file...
F.
Explanation of Solution
SQL server recovery models:
There are three different types of recovery models in SQL server. They are,
- Simple
- Full
- Bulk-logged
Simple:
Simple recovery model helps to maintains smallest quantity of information in transaction log.
- Simple recovery model restores the data from full or differential backups. It requires less administration power and easy to manage than full or bulk-logged model.
- It expense high data loss when data file damages occurs.
- The benefits allows the high-performance copy operation.
- The drawback of the simple model is changes because database or differential backup must need to be rebuild...

Want to see the full answer?
Check out a sample textbook solution
Chapter 6 Solutions
Database Concepts (8th Edition)
- Question 1 (15 Points) Inheritance: In this question, we are going to create a new subclass of the SimpleGeometricObject class, named Triangle. Create a SimpleGeometricObject.java and Copy the source code of the SimpleGeometricObject class from the following link: https://liveexample.pearsoncmg.com/html/SimpleGeometricObject.html TASK 1: Create a Triangle class that extends the SimpleGeometricObject class in Eclipse, following the below UML diagram. + base:double = 5 + height:double = 10 Triangle + Triangle() + Triangle(newBase: double, newHeight: double) + getArea(): double + setBase(): void + setHeight(): void + getBase(): double + getHeight(): doublearrow_forwardQuestion 2 (10 Points): String vs. StringBuilder Create a Question2.java file and finish the following tasks: Task 1. a) Create a 1D array of integers to store 50 integers. b) Store values from 0 to 49 in the array you just created. c) Create a new String Object using no-arg constructor. d) Using for loop to add the array elements one by one to the String (one per loop iteration) Hint: to append an element to a String, use the + operator. e) Output the String on the console. Record and display a run-time it took to append all integers to the String (record run-time of 1.d.)). Please submit a screenshot. The screenshot should match the following example: 012345678910111213141516171819202122232425262728293031323334353637383940414243444546474849 it took 196708 nanoseconds to append 50 integers to the String.| Hint: You can use the following statements to record run-time. long begin, end, time; // we will measure time it took begin = System.nanoTime(); //we measure in nanoseconds. // put…arrow_forwardAnswer this Java OOP question below: Discuss the challenges and benefits of using multiple levels of inheritance in a class hierarchy. How can deep inheritance structures impact the maintainability and readability of code?arrow_forward
- Answer the Java OOP question below: Explain the relationship between a superclass and a subclass. How do the principles of encapsulation and abstraction play a role in this relationship? In your experience, how do you decide what should be included in a superclass versus a subclass? Share an example where a well-defined superclass-subclass hierarchy improved your code.arrow_forward1.) Consider the problem of determining whether a DFA and a regular expression are equivalent. Express this problem as a language and show that it is decidable. ii) Let ALLDFA = {(A)| A is a DFA and L(A) = "}. Show that ALLDFA is decidable. iii) Let AECFG = {(G)| G is a CFG that generates &}. Show that AECFG is decidable. iv) Let ETM {(M)| M is a TM and L(M) = 0}. Show that ETM, the complement of Erm, is Turing-recognizable. Let X be the set {1, 2, 3, 4, 5} and Y be the set {6, 7, 8, 9, 10). We describe the functions f: XY and g: XY in the following tables. Answer each part and give a reason for each negative answer. n f(n) n g(n) 1 6 1 10 2 7 2 9 3 6 3 8 4 7 4 7 5 6 5 6 Aa. Is f one-to-one? b. Is fonto? c. Is fa correspondence? Ad. Is g one-to-one? e. Is g onto? f. Is g a correspondence? vi) Let B be the set of all infinite sequences over {0,1}. Show that B is uncountable using a proof by diagonalization.arrow_forwardCan you find the least amount of different numbers to pick from positive numbers (integers) that are at most 100 to confirm two numbers that add up to 101 when each number can be picked at most two times?arrow_forward
- Can you find the formula for an that satisfies the provided recursive definition? Please show all steps and justificationarrow_forwardWhat is the number of injective functions f from set {1,2,....,2n} to set {1,2,....,2n} so that f(x) >= x for all the 1<= x <= n?arrow_forwardIdeal MOSFET Current–Voltage Characteristics—NMOS Device and draw the circuitarrow_forward
- 1. Create a Person.java file. Implement the public Person and Student classes in Person.java, including all the variables and methods in the UMLS. Person -name: String -street: String -city: String +Person(String name, String, street, String, city) +getName(): String +setName(String name): void +getStreet(): String +setStreet(String street): void +getCity(): String +setCity(String City): void +toString(): String Student -Id: int +Person(String name, String, street, String, city, int Id) +getId(): int +setId(int Id): void +toString(): String 2. Create a StudentTest.java file. Implement a public StudentTest class with a main method. In the main method, create one student object and print the object using System.out.println(). Your printing result must follow the example output: name: Mike, street: Morris Ave, city: Union, Id: 1000 Hint: You need to modify the toString methods in the Student class and Person class!arrow_forward1) Apply the Paint Blue algorithm discussed in class to the following Finite Automata. a a a b b a COIS-3050H-R-W01-2025WI-COMB Formal Languages & Automata a b Show the status of the Finite Automata at the conclusion of the Paint Blue Algorithm (mark the visited states with an X and only include edges that have not been followed). 2) Use the pumping lemma to prove the following language is nonregular: L= {ab} = {abbb, aabbbbbb, aaabbbbbbbbb, ...}arrow_forward3) Find CFGs that for these regular languages over the alphabet Σ= {a, b}. Draw a Finite Automata e CFG. 1 COIS-3050H-R-W01-2025WI-COMB Formal anguages & Automata Is that contain the substring aba. (b) The language of all words that have an odd number letters and contains the string bb. (c) The language of all words that begin with the substring ba and contains an odd number of letters. 4) Convert the following FA into a PDA. a a S± b a a Ν Ꮓarrow_forward
- Database Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781305627482Author:Carlos Coronel, Steven MorrisPublisher:Cengage LearningDatabase Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781285196145Author:Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos CoronelPublisher:Cengage LearningA Guide to SQLComputer ScienceISBN:9781111527273Author:Philip J. PrattPublisher:Course Technology Ptr
- Principles of Information Systems (MindTap Course...Computer ScienceISBN:9781305971776Author:Ralph Stair, George ReynoldsPublisher:Cengage LearningPrinciples of Information Systems (MindTap Course...Computer ScienceISBN:9781285867168Author:Ralph Stair, George ReynoldsPublisher:Cengage Learning





