Data Definition Language
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On-Line Computing with a Hierarchy of Processors
University of Pennsylvania ScholarlyCommons Technical Reports (CIS) Department of Computer & Information Science December 1968 On-Line Computing With a Hierarchy of Processors Richard P. Morton University of Pennsylvania Follow this and additional works at: https://repository.upenn.edu/cis_reports Recommended Citation Richard P. Morton, "On-Line Computing With a Hierarchy of Processors", . December 1968. University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-69-13. This paper is posted at ScholarlyCommons. https://repository.upenn.edu/cis_reports/804 For more information, please contact [email protected]. On-Line Computing With a Hierarchy of Processors Abstract Time shared computer systems have been based upon the two techniques of multiprogramming and swapping. Multiprogramming is based on restricting each program to a portion of the total computer memory. Swapping requires considerable overhead time for loading and unloading programs. To alleviate the size restriction due to multiprogramming, segmentation is employed, resulting in fact in vastly increased swapping. A new system architecture is proposed for time shared computing that alleviates the high overhead or program size restriction. It utilizes a hierarchy of processors, where each processor is assigned tasks on the basis of four factors: interactive requirements, frequency of use, execution time, and program length. In order to study the hierarchical approach to system architecture, the Moore School Problem Solving Facility (MSPSF) was built and used. The study of the manner of operation and the reactions of the users clarified and defined the Hierarchy of Processors system architecture. The Moore School Problem Solving Facility was implemented on second generation equipment, the IBM 7040, and therefore it is not possible to adequately compare the efficiency with third generation computers operating in a swapping mode. -
Referential Integrity in Sqlite
CS 564: Database Management Systems University of Wisconsin - Madison, Fall 2017 Referential Integrity in SQLite Declaring Referential Integrity (Foreign Key) Constraints Foreign key constraints are used to check referential integrity between tables in a database. Consider, for example, the following two tables: create table Residence ( nameVARCHARPRIMARY KEY, capacityINT ); create table Student ( idINTPRIMARY KEY, firstNameVARCHAR, lastNameVARCHAR, residenceVARCHAR ); We can enforce the constraint that a Student’s residence actually exists by making Student.residence a foreign key that refers to Residence.name. SQLite lets you specify this relationship in several different ways: create table Residence ( nameVARCHARPRIMARY KEY, capacityINT ); create table Student ( idINTPRIMARY KEY, firstNameVARCHAR, lastNameVARCHAR, residenceVARCHAR, FOREIGNKEY(residence) REFERENCES Residence(name) ); or create table Residence ( nameVARCHARPRIMARY KEY, capacityINT ); create table Student ( idINTPRIMARY KEY, firstNameVARCHAR, lastNameVARCHAR, residenceVARCHAR REFERENCES Residence(name) ); or create table Residence ( nameVARCHARPRIMARY KEY, 1 capacityINT ); create table Student ( idINTPRIMARY KEY, firstNameVARCHAR, lastNameVARCHAR, residenceVARCHAR REFERENCES Residence-- Implicitly references the primary key of the Residence table. ); All three forms are valid syntax for specifying the same constraint. Constraint Enforcement There are a number of important things about how referential integrity and foreign keys are handled in SQLite: • The attribute(s) referenced by a foreign key constraint (i.e. Residence.name in the example above) must be declared UNIQUE or as the PRIMARY KEY within their table, but this requirement is checked at run-time, not when constraints are declared. For example, if Residence.name had not been declared as the PRIMARY KEY of its table (or as UNIQUE), the FOREIGN KEY declarations above would still be permitted, but inserting into the Student table would always yield an error. -
(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. -
The Unconstrained Primary Key
IBM Systems Lab Services and Training The Unconstrained Primary Key Dan Cruikshank www.ibm.com/systems/services/labservices © 2009 IBM Corporation In this presentation I build upon the concepts that were presented in my article “The Keys to the Kingdom”. I will discuss how primary and unique keys can be utilized for something other than just RI. In essence, it is about laying the foundation for data centric programming. I hope to convey that by establishing some basic rules the database developer can obtain reasonable performance. The title is an oxymoron, in essence a Primary Key is a constraint, but it is a constraint that gives the database developer more freedom to utilize an extremely powerful relational database management system, what we call DB2 for i. 1 IBM Systems Lab Services and Training Agenda Keys to the Kingdom Exploiting the Primary Key Pagination with ROW_NUMBER Column Ordering Summary 2 www.ibm.com/systems/services/labservices © 2009 IBM Corporation I will review the concepts I introduced in the article “The Keys to the Kingdom” published in the Centerfield. I think this was the inspiration for the picture. I offered a picture of me sitting on the throne, but that was rejected. I will follow this with a discussion on using the primary key as a means for creating peer or subset tables for the purpose of including or excluding rows in a result set. The ROW_NUMBER function is part of the OLAP support functions introduced in 5.4. Here I provide some examples of using ROW_NUMBER with the BETWEEN predicate in order paginate a result set. -
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. -
Pizza Parlor Point-Of-Sales System CMPS 342 Database
1 Pizza Parlor Point-Of-Sales System CMPS 342 Database Systems Chris Perry Ruben Castaneda 2 Table of Contents PHASE 1 1 Pizza Parlor: Point-Of-Sales Database........................................................................3 1.1 Description of Business......................................................................................3 1.2 Conceptual Database.........................................................................................4 2 Conceptual Database Design........................................................................................5 2.1 Entities................................................................................................................5 2.2 Relationships....................................................................................................13 2.3 Related Entities................................................................................................16 PHASE 2 3 ER-Model vs Relational Model..................................................................................17 3.1 Description.......................................................................................................17 3.2 Comparison......................................................................................................17 3.3 Conversion from E-R model to relational model.............................................17 3.4 Constraints........................................................................................................19 4 Relational Model..........................................................................................................19 -
Origins of Operating Systems OS/360 Martin Grund
Origins of Operating Systems OS/360 Martin Grund HPI Table of Contents ● IBM System 360 ● Functional Structure of OS/360 ● Virtual Machine Time Sharing Juni 2006 Origins of Operating Systems - OS/360 2 Martin Grund Welcome to Big Blue Juni 2006 Origins of Operating Systems - OS/360 3 Martin Grund IBM System 360 ● In 1964 IBM announced the IBM-360 family for computers ● All machines, despite their differences, had the same user instruction set ● Different operating systems available for these machines ● Only midrange and high-end system run OS/360 ● IBM introduced the new term of hardware architecture ● In 1970 IBM announced System 370 with hardware virtual memory support Juni 2006 Origins of Operating Systems - OS/360 4 Martin Grund IBM System 360 ● High-end machines established 32 bit as standard for computers ● Virtual Memory Support – hardware support for dynamic address translation ● Within ten years S/360 achieved standard status ● Flashback prices: ● 1970 – $279/MB hard disk ● 1980 - $35/MB hard disk | $50.000 /MB DRAM Juni 2006 Origins of Operating Systems - OS/360 5 Martin Grund IBM System 360 Specials ● Introduced 8bit entities ● Introduction of 32 or 64 bit floating point words based on a hexadecimal base ● Variable length strings using length field in the first byte ● All registers are universal registers – accumulators as well as address registers ● Registers use 32 bit, 24 bit for addressing -> 16MB Juni 2006 Origins of Operating Systems - OS/360 6 Martin Grund IBM S/360 - Pictures Juni 2006 Origins of Operating Systems - -
SQL Vs Nosql: a Performance Comparison
SQL vs NoSQL: A Performance Comparison Ruihan Wang Zongyan Yang University of Rochester University of Rochester [email protected] [email protected] Abstract 2. ACID Properties and CAP Theorem We always hear some statements like ‘SQL is outdated’, 2.1. ACID Properties ‘This is the world of NoSQL’, ‘SQL is still used a lot by We need to refer the ACID properties[12]: most of companies.’ Which one is accurate? Has NoSQL completely replace SQL? Or is NoSQL just a hype? SQL Atomicity (Structured Query Language) is a standard query language A transaction is an atomic unit of processing; it should for relational database management system. The most popu- either be performed in its entirety or not performed at lar types of RDBMS(Relational Database Management Sys- all. tems) like Oracle, MySQL, SQL Server, uses SQL as their Consistency preservation standard database query language.[3] NoSQL means Not A transaction should be consistency preserving, meaning Only SQL, which is a collection of non-relational data stor- that if it is completely executed from beginning to end age systems. The important character of NoSQL is that it re- without interference from other transactions, it should laxes one or more of the ACID properties for a better perfor- take the database from one consistent state to another. mance in desired fields. Some of the NOSQL databases most Isolation companies using are Cassandra, CouchDB, Hadoop Hbase, A transaction should appear as though it is being exe- MongoDB. In this paper, we’ll outline the general differences cuted in iso- lation from other transactions, even though between the SQL and NoSQL, discuss if Relational Database many transactions are execut- ing concurrently. -
Applying the ETL Process to Blockchain Data. Prospect and Findings
information Article Applying the ETL Process to Blockchain Data. Prospect and Findings Roberta Galici 1, Laura Ordile 1, Michele Marchesi 1 , Andrea Pinna 2,* and Roberto Tonelli 1 1 Department of Mathematics and Computer Science, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy; [email protected] (R.G.); [email protected] (L.O.); [email protected] (M.M.); [email protected] (R.T.) 2 Department of Electrical and Electronic Engineering (DIEE), University of Cagliari, Piazza D’Armi, 09100 Cagliari, Italy * Correspondence: [email protected] Received: 7 March 2020; Accepted: 7 April 2020; Published: 10 April 2020 Abstract: We present a novel strategy, based on the Extract, Transform and Load (ETL) process, to collect data from a blockchain, elaborate and make it available for further analysis. The study aims to satisfy the need for increasingly efficient data extraction strategies and effective representation methods for blockchain data. For this reason, we conceived a system to make scalable the process of blockchain data extraction and clustering, and to provide a SQL database which preserves the distinction between transaction and addresses. The proposed system satisfies the need to cluster addresses in entities, and the need to store the extracted data in a conventional database, making possible the data analysis by querying the database. In general, ETL processes allow the automation of the operation of data selection, data collection and data conditioning from a data warehouse, and produce output data in the best format for subsequent processing or for business. We focus on the Bitcoin blockchain transactions, which we organized in a relational database to distinguish between the input section and the output section of each transaction. -
IBM Application System/400 System/38-Compatible COBOL User's Guide and Reference
IBM IBM Application System/400 SC09-1814-00 System/38-Compatible COBOL User’s Guide and Reference Note! Before using this information and the product it supports, be sure to read the general information under “Notices” on page xv. First Edition (June 1994) This edition applies to the System/38-Compatible feature of the IBM* ILE* COBOL/400* licensed program, (Program 5763-CB1), Version 3 Release 0 Modification 5, and to all subsequent releases and modifications until otherwise indi- cated in new editions. Make sure you are using the proper edition for the level of the product. Order publications through your IBM representative or the IBM branch serving your locality. Publications are not stocked at the address given below. A form for readers’ comments is provided at the back of this publication. If the form has been removed, you may address your comments to: IBM Canada Ltd. Laboratory Information Development 2G/345/1150/TOR 1150 Eglinton Avenue East, North York, Ontario, Canada M3C1H7 You can also send your comments by facsimile (attention: RCF Coordinator), or you can send your comments elec- tronically to IBM. See "Communicating your Comments to IBM" for a description of the methods. This page imme- diately precedes the Readers' Comment Form at the back of this publication. When you send information to IBM, you grant IBM a non-exclusive right to use or distribute the information in any way it believes appropriate without incurring any obligation to you. Copyright International Business Machines Corporation 1994. All rights reserved. Note to U.S. Government Users — Documentation related to restricted rights — Use, duplication or disclosure is subject to restrictions set forth in GSA ADP Schedule Contract with IBM Corp. -
The Temporal Query Language Tquel
The Temporal Query Language TQuel RICHARD SNODGRASS University of North Carolina Recently, attention has been focused on temporal datubases, representing an enterprise over time. We have developed a new language, TQuel, to query a temporal database. TQuel was designed to be a minimal extension, both syntactically and semantically, of Quel, the query language in the Ingres relational database management system. This paper discusses the language informally, then provides a tuple relational calculus semantics for the TQuel statements that differ from their Quel counterparts, including the modification statements. The three additional temporal constructs defined in TQuel are shown to be direct semantic analogues of Quel’s where clause and target list. We also discuss reducibility of the semantics to Quel’s semantics when applied to a static database. TQuel is compared with ten other query languages supporting time. Categories and Subject Descriptors: H.2.1 [Database Management]: Logical Design-data models; H.2.3 [Database Management]: Languages-query lunguages; H.2.7 [Database Management]: Database Administration-logging and recovery General Terms: Languages, Theory Additional Key Words and Phrases: Historical database, Quel, relational calculus, relational model, rollback database, temporal database, tuple calculus 1. INTRODUCTION Most conventional databases represent the state of an enterprise at a single moment of time. Although the contents of the database continue to change as new information is added, these changes are viewed as modifications to the state, with the old, out-of-date data being deleted from the database. The current contents of the database may be viewed as a snapshot of the enterprise. Recently, attention has been focused on temporal dutubases (Z’DBs), repre- senting the progression of states of an enterprise over an interval of time. -
Preparation of Papers for AIAA Technical Conferences
NASA KSC – Internship Final Report Unit Testing and Remote Display Development Nicholas Costa Kennedy Space Center Computer Science USRA Summer Session 18 07 2014 NASA Center 1 18/7/2014 NASA KSC – Internship Final Report Unit Testing and Remote Display Development Nicholas Costa Denison University, Granville, Ohio, Abstract The Kennedy Space Center is currently undergoing an extremely interesting transitional phase. The final Space Shuttle mission, STS-135, was completed in July of 2011. NASA is now approaching a new era of space exploration. The development of the Orion Multi- Purpose Crew Vehicle (MPCV) and the Space Launch System (SLS) launch vehicle that will launch the Orion are currently in progress. An important part of this transition involves replacing the Launch Processing System (LPS) which was previously used to process and launch Space Shuttles and their associated hardware. NASA is creating the Spaceport Command and Control System (SCCS) to replace the LPS. The SCCS will be much simpler to maintain and improve during the lifetime of the spaceflight program that it will support. The Launch Control System (LCS) is a portion of the SCCS that will be responsible for launching the rockets and spacecraft. The Integrated Launch Operations Applications (ILOA) group of SCCS is responsible for creating displays and scripts, both remote and local, that will be used to monitor and control hardware and systems needed to launch a spacecraft. It is crucial that the software contained within be thoroughly tested to ensure that it functions as intended. Unit tests must be written in Application Control Language (ACL), the scripting language used by LCS.