CONCEPTS OF DATABASE MANAGEMENT
9th Edition
ISBN: 9780357261354
Author: Pratt
Publisher: CENGAGE C
expand_more
expand_more
format_list_bulleted
Question
Chapter 6, Problem 11RQ
To determine
To describe the relationship between columns that are null and entity subtypes and explain the circumstances for these columns that lead to more than one entity subtype.
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
Activity No.
Activity
Time (weeks)
Immediate Predecessors
1
Requirements collection
3
2
Requirements structuring
4
1
3
Process analysis
3
2
4
Data analysis
3
2
5
Logical design
50
3,4
6
Physical design
5
5
7
Implementation
6
6
c. Using the information from part b, prepare a network diagram. Identify the critical path.
Given the following Extended-BNF grammar of the basic mathematical expressions:
Show the derivation steps for the expression: ( 2 + 3 ) * 6 – 20 / ( 3 + 1 )
Draw the parsing tree of this expression.
SEE IMAGE
Whentheuserenters!!,themostrecentcommandinthehistoryisexecuted.In the example above, if the user entered the command:
Osh> !!
The ‘ls -l’ command should be executed and echoed on user’s screen. The command should also be placed in the history buffer as the next command.
Whentheuserentersasingle!followedbyanintegerN,theNthcommandin the history is executed. In the example above, if the user entered the command:
Osh> ! 3
The ‘ps’ command should be executed and echoed on the user’s screen. The command should also be placed in the history buffer as the next command.
Error handling:
The program should also manage basic error handling. For example, if there are no commands in the history, entering !! should result in a message “No commands in history.” Also, if there is no command corresponding to the number entered with the single !, the program should output "No such command in history."
Chapter 6 Solutions
CONCEPTS OF DATABASE MANAGEMENT
Knowledge Booster
Similar questions
- Activity No. Activity Time (weeks) Immediate Predecessors 1 Requirements collection 3 2 Requirements structuring 4 1 3 Process analysis 3 2 4 Data analysis 3 2 5 Logical design 50 3,4 6 Physical design 5 5 7 Implementation 6 6 c. Using the information from part b, prepare a network diagram. Identify the critical path.arrow_forward2. UNIX Shell and History Feature [20 points] This question consists of designing a C program to serve as a shell interface that accepts user commands and then executes each command in a separate process. A shell interface gives the user a prompt, after which the next command is entered. The example below illustrates the prompt osh> and the user's next command: cat prog.c. The UNIX/Linux cat command displays the contents of the file prog.c on the terminal using the UNIX/Linux cat command and your program needs to do the same. osh> cat prog.c The above can be achieved by running your shell interface as a parent process. Every time a command is entered, you create a child process by using fork(), which then executes the user's command using one of the system calls in the exec() family (as described in Chapter 3). A C program that provides the general operations of a command-line shell can be seen below. #include #include #define MAX LINE 80 /* The maximum length command */ { int…arrow_forwardQuestion#2: Design and implement a Java program using Abstract Factory and Singleton design patterns. The program displays date and time in one of the following two formats: Format 1: Date: MM/DD/YYYY Time: HH:MM:SS Format 2: Date: DD-MM-YYYY Time: SS,MM,HH The following is how the program works. In the beginning, the program asks the user what display format that she wants. Then the program continuously asks the user to give one of the following commands, and performs the corresponding task. Note that the program gets the current date and time from the system clock (use the appropriate Java date and time operations for this). 'd' display current date 't': display current time 'q': quit the program. • In the program, there should be 2 product hierarchies: "DateObject” and “TimeObject”. Each hierarchy should have format and format2 described above. • Implement the factories as singletons. • Run your code and attach screenshots of the results. • Draw a UML class diagram for the program.arrow_forward
- #include <linux/module.h> #include <linux/kernel.h> // part 2 #include <linux/sched.h> // part 2 extra #include <linux/hash.h> #include <linux/gcd.h> #include <asm/param.h> #include <linux/jiffies.h> void print_init_PCB(void) { printk(KERN_INFO "init_task pid:%d\n", init_task.pid); printk(KERN_INFO "init_task state:%lu\n", init_task.state); printk(KERN_INFO "init_task flags:%d\n", init_task.flags); printk(KERN_INFO "init_task runtime priority:%d\n", init_task.rt_priority); printk(KERN_INFO "init_task process policy:%d\n", init_task.policy); printk(KERN_INFO "init_task task group id:%d\n", init_task.tgid); } /* This function is called when the module is loaded. */ int simple_init(void) { printk(KERN_INFO "Loading Module\n"); print_init_PCB(); printk(KERN_INFO "Golden Ration Prime = %lu\n", GOLDEN_RATIO_PRIME); printk(KERN_INFO "HZ = %d\n", HZ); printk(KERN_INFO "enter jiffies = %lu\n", jiffies); return 0; } /* This function is called when the…arrow_forwardList at least five Operating Systems you know. What is the difference between the kernel mode and the user mode for the Linux? What is the system-call? Give an example of API in OS that use the system-call. What is cache? Why the CPU has cache? What is the difference between the Static Linking and Dynamic Linking when compiling the code.arrow_forwardIn the GoF book, List interface is defined as follows: interface List { int count(); //return the current number of elements in the list Object get(int index); //return the object at the index in the list Object first(); //return the first object in the list Object last(); //return the last object in the list boolean include(Object obj); //return true is the object in the list void append(Object obj); //append the object to the end of the list void prepend(Object obj); //insert the object to the front of the list void delete(Object obj); //remove the object from the list void deleteLast(); //remove the last element of the list void deleteFirst(); //remove the first element of the list void deleteAll(); //remove all elements of the list (a) Write a class adapter to adapt Java ArrayList to GoF List interface. (b) Write a main program to test your adapters through List interface. (c) Same requirement as (a) and (b), but write an object adapter to adapt Java ArrayList to GoF List…arrow_forward
- In modern packet-switched networks, including the Internet, the source host segments long, application-layer messages (for example, an image or a music file) into smaller packets and sends the packets into the network. The receiver then reassembles the packets back into the original message. We refer to this process as message segmentation. Figure 1.27 (attached) illustrates the end-to-end transport of a message with and without message segmentation. Consider a message that is 106 bits long that is to be sent from source to destination in Figure 1.27. Suppose each link in the figure is 5 Mbps. Ignore propagation, queuing, and processing delays. a. Consider sending the message from source to destination without message segmentation. How long does it take to move the message from the source host to the first packet switch? Keeping in mind that each switch uses store-and-forward packet switching, what is the total time to move the message from source host to destination host? b. Now…arrow_forwardConsider a packet of length L that begins at end system A and travels over three links to a destination end system. These three links are connected by two packet switches. Let di, si, and Ri denote the length, propagation speed, and the transmission rate of link i, for i = 1, 2, 3. The packet switch delays each packet by dproc. Assuming no queuing delays, in terms of di, si, Ri, (i = 1, 2, 3), and L, what is the total end-to-end delay for the packet? Suppose now the packet is 1,500 bytes, the propagation speed on all three links is 2.5 * 10^8 m/s, the transmission rates of all three links are 2.5 Mbps, the packet switch processing delay is 3 msec, the length of the first link is 5,000 km, the length of the second link is 4,000 km, and the length of the last link is 1,000 km. For these values, what is the end-to-end delay?arrow_forwardhow to know the weight to data and data to weight also weight by infomraion gain in rapid miner , between this flow diagram retrieve then selecte attrbuite then set role and split data and decision tree and apply model and peformance ,please show how the operators should be connected:arrow_forward
- using rapid miner how to creat decison trea for all attribute and another one with delete one or more of them also how i know the weight of each attribute and what that mean in impact the resultarrow_forwardQ.1. Architecture performance [10 marks] Answer A certain microprocessor requires either 2, 4, or 6 machine cycles to perform various operations. ⚫ (40+g+f)% require 2 machine cycles, ⚫ (30-g) % require 4 machine cycles, and ⚫ (30-f)% require 6 machine cycles. (a) What is the average number of machine cycles per instruction for this microprocessor? Answer (b) What is the clock rate (machine cycles per second) required for this microprocessor to be a "1000 MIPS" processor? Answer (c) Suppose that 35% of the instructions require retrieving an operand from memory which needs an extra 8 machine cycles. What is the average number of machine cycles per instruction, including the instructions that fetch operands from memory?arrow_forwardQ.2. Architecture performance [25 marks] Consider two different implementations, M1 and M2, of the same instruction set. M1 has a clock rate of 2 GHz and M2 has a clock rate of 3.3 GHz. There are two classes of instructions with the following CPIs: Class A CPI for M1 CPI for M2 2.f 1.g B 5 3 C 6 4 Note that the dots in 2 fand 1.g indicate decimal points and not multiplication. a) What are the peak MIPS performances for both machines? b) Which implementation is faster, if half the instructions executed in a certain program are from class A, while the rest are divided equally among classes B and C. c) What speedup factor for the execution of class-A instructions would lead to 20% overall speedup? d) What is the maximum possible speedup that can be achieved by only improving the execution of class-A instructions? Explain why. e) What is the clock rate required for microprocessor M1 to be a "1000 MIPS" (not peak MIPS) processor?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Information Systems (MindTap Course...Computer ScienceISBN:9781305971776Author:Ralph Stair, George ReynoldsPublisher:Cengage Learning
Database Systems: Design, Implementation, & Manag...Computer ScienceISBN:9781305627482Author:Carlos Coronel, Steven MorrisPublisher:Cengage Learning
Database 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 Learning
Principles of Information Systems (MindTap Course...Computer ScienceISBN:9781285867168Author:Ralph Stair, George ReynoldsPublisher:Cengage Learning
Fundamentals of Information SystemsComputer ScienceISBN:9781337097536Author:Ralph Stair, George ReynoldsPublisher:Cengage Learning
A Guide to SQLComputer ScienceISBN:9781111527273Author:Philip J. PrattPublisher:Course Technology Ptr
Principles of Information Systems (MindTap Course...
Computer Science
ISBN:9781305971776
Author:Ralph Stair, George Reynolds
Publisher:Cengage Learning
Database Systems: Design, Implementation, & Manag...
Computer Science
ISBN:9781305627482
Author:Carlos Coronel, Steven Morris
Publisher:Cengage Learning
Database Systems: Design, Implementation, & Manag...
Computer Science
ISBN:9781285196145
Author:Steven, Steven Morris, Carlos Coronel, Carlos, Coronel, Carlos; Morris, Carlos Coronel and Steven Morris, Carlos Coronel; Steven Morris, Steven Morris; Carlos Coronel
Publisher:Cengage Learning
Principles of Information Systems (MindTap Course...
Computer Science
ISBN:9781285867168
Author:Ralph Stair, George Reynolds
Publisher:Cengage Learning
Fundamentals of Information Systems
Computer Science
ISBN:9781337097536
Author:Ralph Stair, George Reynolds
Publisher:Cengage Learning
A Guide to SQL
Computer Science
ISBN:9781111527273
Author:Philip J. Pratt
Publisher:Course Technology Ptr