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An Overview of the 50 Most Common Web Scraping Tools
AN OVERVIEW OF THE 50 MOST COMMON WEB SCRAPING TOOLS WEB SCRAPING IS THE PROCESS OF USING BOTS TO EXTRACT CONTENT AND DATA FROM A WEBSITE. UNLIKE SCREEN SCRAPING, WHICH ONLY COPIES PIXELS DISPLAYED ON SCREEN, WEB SCRAPING EXTRACTS UNDERLYING CODE — AND WITH IT, STORED DATA — AND OUTPUTS THAT INFORMATION INTO A DESIGNATED FILE FORMAT. While legitimate uses cases exist for data harvesting, illegal purposes exist as well, including undercutting prices and theft of copyrighted content. Understanding web scraping bots starts with understanding the diverse and assorted array of web scraping tools and existing platforms. Following is a high-level overview of the 50 most common web scraping tools and platforms currently available. PAGE 1 50 OF THE MOST COMMON WEB SCRAPING TOOLS NAME DESCRIPTION 1 Apache Nutch Apache Nutch is an extensible and scalable open-source web crawler software project. A-Parser is a multithreaded parser of search engines, site assessment services, keywords 2 A-Parser and content. 3 Apify Apify is a Node.js library similar to Scrapy and can be used for scraping libraries in JavaScript. Artoo.js provides script that can be run from your browser’s bookmark bar to scrape a website 4 Artoo.js and return the data in JSON format. Blockspring lets users build visualizations from the most innovative blocks developed 5 Blockspring by engineers within your organization. BotScraper is a tool for advanced web scraping and data extraction services that helps 6 BotScraper organizations from small and medium-sized businesses. Cheerio is a library that parses HTML and XML documents and allows use of jQuery syntax while 7 Cheerio working with the downloaded data. -
Data and Computer Communications (Eighth Edition)
DATA AND COMPUTER COMMUNICATIONS Eighth Edition William Stallings Upper Saddle River, New Jersey 07458 Library of Congress Cataloging-in-Publication Data on File Vice President and Editorial Director, ECS: Art Editor: Gregory Dulles Marcia J. Horton Director, Image Resource Center: Melinda Reo Executive Editor: Tracy Dunkelberger Manager, Rights and Permissions: Zina Arabia Assistant Editor: Carole Snyder Manager,Visual Research: Beth Brenzel Editorial Assistant: Christianna Lee Manager, Cover Visual Research and Permissions: Executive Managing Editor: Vince O’Brien Karen Sanatar Managing Editor: Camille Trentacoste Manufacturing Manager, ESM: Alexis Heydt-Long Production Editor: Rose Kernan Manufacturing Buyer: Lisa McDowell Director of Creative Services: Paul Belfanti Executive Marketing Manager: Robin O’Brien Creative Director: Juan Lopez Marketing Assistant: Mack Patterson Cover Designer: Bruce Kenselaar Managing Editor,AV Management and Production: Patricia Burns ©2007 Pearson Education, Inc. Pearson Prentice Hall Pearson Education, Inc. Upper Saddle River, NJ 07458 All rights reserved. No part of this book may be reproduced in any form or by any means, without permission in writing from the publisher. Pearson Prentice Hall™ is a trademark of Pearson Education, Inc. All other tradmarks or product names are the property of their respective owners. The author and publisher of this book have used their best efforts in preparing this book.These efforts include the development, research, and testing of the theories and programs to determine their effectiveness.The author and publisher make no warranty of any kind, expressed or implied, with regard to these programs or the documentation contained in this book.The author and publisher shall not be liable in any event for incidental or consequential damages in connection with, or arising out of, the furnishing, performance, or use of these programs. -
(DDL) Reference Manual
Data Definition Language (DDL) Reference Manual Abstract This publication describes the DDL language syntax and the DDL dictionary database. The audience includes application programmers and database administrators. Product Version DDL D40 DDL H01 Supported Release Version Updates (RVUs) This publication supports J06.03 and all subsequent J-series RVUs, H06.03 and all subsequent H-series RVUs, and G06.26 and all subsequent G-series RVUs, until otherwise indicated by its replacement publications. Part Number Published 529431-003 May 2010 Document History Part Number Product Version Published 529431-002 DDL D40, DDL H01 July 2005 529431-003 DDL D40, DDL H01 May 2010 Legal Notices Copyright 2010 Hewlett-Packard Development Company L.P. Confidential computer software. Valid license from HP required for possession, use or copying. Consistent with FAR 12.211 and 12.212, Commercial Computer Software, Computer Software Documentation, and Technical Data for Commercial Items are licensed to the U.S. Government under vendor's standard commercial license. The information contained herein is subject to change without notice. The only warranties for HP products and services are set forth in the express warranty statements accompanying such products and services. Nothing herein should be construed as constituting an additional warranty. HP shall not be liable for technical or editorial errors or omissions contained herein. Export of the information contained in this publication may require authorization from the U.S. Department of Commerce. Microsoft, Windows, and Windows NT are U.S. registered trademarks of Microsoft Corporation. Intel, Itanium, Pentium, and Celeron are trademarks or registered trademarks of Intel Corporation or its subsidiaries in the United States and other countries. -
Failures in DBMS
Chapter 11 Database Recovery 1 Failures in DBMS Two common kinds of failures StSystem filfailure (t)(e.g. power outage) ‒ affects all transactions currently in progress but does not physically damage the data (soft crash) Media failures (e.g. Head crash on the disk) ‒ damagg()e to the database (hard crash) ‒ need backup data Recoveryyp scheme responsible for handling failures and restoring database to consistent state 2 Recovery Recovering the database itself Recovery algorithm has two parts ‒ Actions taken during normal operation to ensure system can recover from failure (e.g., backup, log file) ‒ Actions taken after a failure to restore database to consistent state We will discuss (briefly) ‒ Transactions/Transaction recovery ‒ System Recovery 3 Transactions A database is updated by processing transactions that result in changes to one or more records. A user’s program may carry out many operations on the data retrieved from the database, but the DBMS is only concerned with data read/written from/to the database. The DBMS’s abstract view of a user program is a sequence of transactions (reads and writes). To understand database recovery, we must first understand the concept of transaction integrity. 4 Transactions A transaction is considered a logical unit of work ‒ START Statement: BEGIN TRANSACTION ‒ END Statement: COMMIT ‒ Execution errors: ROLLBACK Assume we want to transfer $100 from one bank (A) account to another (B): UPDATE Account_A SET Balance= Balance -100; UPDATE Account_B SET Balance= Balance +100; We want these two operations to appear as a single atomic action 5 Transactions We want these two operations to appear as a single atomic action ‒ To avoid inconsistent states of the database in-between the two updates ‒ And obviously we cannot allow the first UPDATE to be executed and the second not or vice versa. -
SQL Server Column Store Indexes Per-Åke Larson, Cipri Clinciu, Eric N
SQL Server Column Store Indexes Per-Åke Larson, Cipri Clinciu, Eric N. Hanson, Artem Oks, Susan L. Price, Srikumar Rangarajan, Aleksandras Surna, Qingqing Zhou Microsoft {palarson, ciprianc, ehans, artemoks, susanpr, srikumar, asurna, qizhou}@microsoft.com ABSTRACT SQL Server column store indexes are “pure” column stores, not a The SQL Server 11 release (code named “Denali”) introduces a hybrid, because they store all data for different columns on new data warehouse query acceleration feature based on a new separate pages. This improves I/O scan performance and makes index type called a column store index. The new index type more efficient use of memory. SQL Server is the first major combined with new query operators processing batches of rows database product to support a pure column store index. Others greatly improves data warehouse query performance: in some have claimed that it is impossible to fully incorporate pure column cases by hundreds of times and routinely a tenfold speedup for a store technology into an established database product with a broad broad range of decision support queries. Column store indexes are market. We’re happy to prove them wrong! fully integrated with the rest of the system, including query To improve performance of typical data warehousing queries, all a processing and optimization. This paper gives an overview of the user needs to do is build a column store index on the fact tables in design and implementation of column store indexes including the data warehouse. It may also be beneficial to build column enhancements to query processing and query optimization to take store indexes on extremely large dimension tables (say more than full advantage of the new indexes. -
Microsoft Office Application Specialist, Short-Term Certificate 1
Microsoft Office Application Specialist, Short-Term Certificate 1 MICROSOFT OFFICE Suggested Semester Sequence Course Title Credit APPLICATION SPECIALIST, Hours Summer Start SHORT-TERM CERTIFICATE Select one of the following: 3 ACCT-1011 Business Math Applications ACCT-1020 Applied Accounting This short-term certificate provides knowledge and skills in preparation Select one of the following: 3 for the Word, Excel, Access, PowerPoint, and Outlook MOS (Microsoft IT-1010 Introduction to Microcomputer Office Specialist) exams. Students enrolled in this certificate program will Applications acquire competencies in advanced word processing, spreadsheet design IT-101H Honors Introduction to Microcomputer and use, presentation software, email application features including Applications calendaring, and database maintenance. Credit Hours 6 Program contact: Learn more (http://www.tri-c.edu/programs/business- First Semester management/business-technology/microsoft-office-specialist-short- BT-1201 Word Processing 3 term-certificate.html) BT-2040 Emerging Workplace Technology 3 This certificate will be automatically awarded when the certificate BT-2210 Presentation Software 2 requirements are completed. If you do not want to receive the certificate, BT-2300 Business Database Systems (Access) 3 please notify the Office of the Registrar at [email protected]. Credit Hours 11 Learn more (http://catalog.tri-c.edu/archives/2017-2018/pathways/ Second Semester business/business-technology) about how certificate credits apply to the BT-2200 Advanced Word Processing 3 related degree. BT-2220 Business Spreadsheet Applications (Excel) 3 Credit Hours 6 Gainful Employment Disclosure (http://www.tri-c.edu/about/disclosure/ Microsoft_Office_Specialist/Gedt.html) Total Credit Hours 23 Students must be able to touch type at a combined speed and accuracy rate of 25 wpm. -
When Relational-Based Applications Go to Nosql Databases: a Survey
information Article When Relational-Based Applications Go to NoSQL Databases: A Survey Geomar A. Schreiner 1,* , Denio Duarte 2 and Ronaldo dos Santos Mello 1 1 Departamento de Informática e Estatística, Federal University of Santa Catarina, 88040-900 Florianópolis - SC, Brazil 2 Campus Chapecó, Federal University of Fronteira Sul, 89815-899 Chapecó - SC, Brazil * Correspondence: [email protected] Received: 22 May 2019; Accepted: 12 July 2019; Published: 16 July 2019 Abstract: Several data-centric applications today produce and manipulate a large volume of data, the so-called Big Data. Traditional databases, in particular, relational databases, are not suitable for Big Data management. As a consequence, some approaches that allow the definition and manipulation of large relational data sets stored in NoSQL databases through an SQL interface have been proposed, focusing on scalability and availability. This paper presents a comparative analysis of these approaches based on an architectural classification that organizes them according to their system architectures. Our motivation is that wrapping is a relevant strategy for relational-based applications that intend to move relational data to NoSQL databases (usually maintained in the cloud). We also claim that this research area has some open issues, given that most approaches deal with only a subset of SQL operations or give support to specific target NoSQL databases. Our intention with this survey is, therefore, to contribute to the state-of-art in this research area and also provide a basis for choosing or even designing a relational-to-NoSQL data wrapping solution. Keywords: big data; data interoperability; NoSQL databases; relational-to-NoSQL mapping 1. -
Keys Are, As Their Name Suggests, a Key Part of a Relational Database
The key is defined as the column or attribute of the database table. For example if a table has id, name and address as the column names then each one is known as the key for that table. We can also say that the table has 3 keys as id, name and address. The keys are also used to identify each record in the database table . Primary Key:- • Every database table should have one or more columns designated as the primary key . The value this key holds should be unique for each record in the database. For example, assume we have a table called Employees (SSN- social security No) that contains personnel information for every employee in our firm. We’ need to select an appropriate primary key that would uniquely identify each employee. Primary Key • The primary key must contain unique values, must never be null and uniquely identify each record in the table. • As an example, a student id might be a primary key in a student table, a department code in a table of all departments in an organisation. Unique Key • The UNIQUE constraint uniquely identifies each record in a database table. • Allows Null value. But only one Null value. • A table can have more than one UNIQUE Key Column[s] • A table can have multiple unique keys Differences between Primary Key and Unique Key: • Primary Key 1. A primary key cannot allow null (a primary key cannot be defined on columns that allow nulls). 2. Each table can have only one primary key. • Unique Key 1. A unique key can allow null (a unique key can be defined on columns that allow nulls.) 2. -
Blockchain Database for a Cyber Security Learning System
Session ETD 475 Blockchain Database for a Cyber Security Learning System Sophia Armstrong Department of Computer Science, College of Engineering and Technology East Carolina University Te-Shun Chou Department of Technology Systems, College of Engineering and Technology East Carolina University John Jones College of Engineering and Technology East Carolina University Abstract Our cyber security learning system involves an interactive environment for students to practice executing different attack and defense techniques relating to cyber security concepts. We intend to use a blockchain database to secure data from this learning system. The data being secured are students’ scores accumulated by successful attacks or defends from the other students’ implementations. As more professionals are departing from traditional relational databases, the enthusiasm around distributed ledger databases is growing, specifically blockchain. With many available platforms applying blockchain structures, it is important to understand how this emerging technology is being used, with the goal of utilizing this technology for our learning system. In order to successfully secure the data and ensure it is tamper resistant, an investigation of blockchain technology use cases must be conducted. In addition, this paper defined the primary characteristics of the emerging distributed ledgers or blockchain technology, to ensure we effectively harness this technology to secure our data. Moreover, we explored using a blockchain database for our data. 1. Introduction New buzz words are constantly surfacing in the ever evolving field of computer science, so it is critical to distinguish the difference between temporary fads and new evolutionary technology. Blockchain is one of the newest and most developmental technologies currently drawing interest. -
CANDIDATE KEYS a Candidate Key of a Relation Schema R Is a Subset X
CANDIDATEKEYS A candidate key of a relation schema R is a subset X of the attributes of R with the following twoproperties: 1. Every attribute is functionally dependent on X, i.e., X + =all attributes of R (also denoted as X + =R). 2. No proper subset of X has the property (1), i.e., X is minimal with respect to the property (1). A sub-key of R: asubset of a candidate key; a super-key:aset of attributes containing a candidate key. We also use the abbreviation CK to denote "candidate key". Let R(ABCDE) be a relation schema and consider the fol- lowing functional dependencies F = {AB → E, AD → B, B → C, C → D}. Since (AC)+ =ABCDE, A+ =A,and C+ =CD, we knowthat ACisacandidate key,both A and C are sub-keys, and ABC is a super-key.The only other candidate keysare AB and AD. Note that since nothing determines A, A is in every can- didate key. -2- Computing All Candidate Keys of a Relation R. Givenarelation schema R(A1, A2,..., An)and a set of functional dependencies F which hold true on R, howcan we compute all candidate keysofR? Since each candidate key must be a minimal subset Z of {A1,..., + An}such that Z =R,wehav e the following straightforward (and brute-force) algorithm: (1) Construct alist L consisting of all non-empty subsets of {A1, n − ..., An}(there are 2 1ofthem). These subsets are arranged in L in ascending order of the size of the subset: 〈 〉 ≤ We get L = Z1, Z2,..., Z2n−1 ,such that |Zi| |Zi+1|. -
Introduction to Computers and Office Productivity Software
Wright State University CORE Scholar Computer Science & Engineering Syllabi College of Engineering & Computer Science Fall 2011 CS 205-08: Introduction to Computers and Office oductivityPr Software Terri Bauer Wright State University - Main Campus, [email protected] Follow this and additional works at: https://corescholar.libraries.wright.edu/cecs_syllabi Part of the Computer Engineering Commons, and the Computer Sciences Commons Repository Citation Bauer, T. (2011). CS 205-08: Introduction to Computers and Office oductivityPr Software. https://corescholar.libraries.wright.edu/cecs_syllabi/363 This Syllabus is brought to you for free and open access by the College of Engineering & Computer Science at CORE Scholar. It has been accepted for inclusion in Computer Science & Engineering Syllabi by an authorized administrator of CORE Scholar. For more information, please contact [email protected]. COURSE SYLLABUS <WEUS Introduction to Computers and Office Productivity Software Fall 2011 General Course Information Instructor: E-mail: [email protected] Classroom: 320 Delman Web site: http://oilot.wright.edu Prerequisites: No course pre-requisites, however a basic understanding of computers and word processing as acquired in high school - is assumed. Credit Hours: 4 Quarter Hours Textbook: New Perspectives Microsoft Office 2010 First Course ISBN: 978-0-538-7463-3 SAM Assessment and Projects Software - comes bundled with book Course Description Focus on learning MS Office software applications including intermediate word processing, spreadsheets, database and presentation graphics using a case study approach where critical thinking and problem solving skills are required. Computer concepts are integrated throughout the course to provide an understanding of the basics of computing, the latest technological advances and how they are used in industry. -
An Introduction to Cloud Databases a Guide for Administrators
Compliments of An Introduction to Cloud Databases A Guide for Administrators Wendy Neu, Vlad Vlasceanu, Andy Oram & Sam Alapati REPORT Break free from old guard databases AWS provides the broadest selection of purpose-built databases allowing you to save, grow, and innovate faster Enterprise scale at 3-5x the performance 14+ database engines 1/10th the cost of vs popular alternatives - more than any other commercial databases provider Learn more: aws.amazon.com/databases An Introduction to Cloud Databases A Guide for Administrators Wendy Neu, Vlad Vlasceanu, Andy Oram, and Sam Alapati Beijing Boston Farnham Sebastopol Tokyo An Introduction to Cloud Databases by Wendy A. Neu, Vlad Vlasceanu, Andy Oram, and Sam Alapati Copyright © 2019 O’Reilly Media Inc. All rights reserved. Printed in the United States of America. Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472. O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions are also available for most titles (http://oreilly.com). For more infor‐ mation, contact our corporate/institutional sales department: 800-998-9938 or [email protected]. Development Editor: Jeff Bleiel Interior Designer: David Futato Acquisitions Editor: Jonathan Hassell Cover Designer: Karen Montgomery Production Editor: Katherine Tozer Illustrator: Rebecca Demarest Copyeditor: Octal Publishing, LLC September 2019: First Edition Revision History for the First Edition 2019-08-19: First Release The O’Reilly logo is a registered trademark of O’Reilly Media, Inc. An Introduction to Cloud Databases, the cover image, and related trade dress are trademarks of O’Reilly Media, Inc. The views expressed in this work are those of the authors, and do not represent the publisher’s views.