Declarative Constraints
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SAP IQ Administration: User Management and Security Company
ADMINISTRATION GUIDE | PUBLIC SAP IQ 16.1 SP 04 Document Version: 1.0.0 – 2019-04-05 SAP IQ Administration: User Management and Security company. All rights reserved. All rights company. affiliate THE BEST RUN 2019 SAP SE or an SAP SE or an SAP SAP 2019 © Content 1 Security Management........................................................ 5 1.1 Plan and Implement Role-Based Security............................................6 1.2 Roles......................................................................7 User-Defined Roles.........................................................8 System Roles............................................................ 30 Compatibility Roles........................................................38 Views, Procedures, and Tables That Are Owned by Roles..............................38 Display Roles Granted......................................................39 Determining the Roles and Privileges Granted to a User...............................40 1.3 Privileges..................................................................40 Privileges Versus Permissions.................................................41 System Privileges......................................................... 42 Object-Level Privileges......................................................64 System Procedure Privileges..................................................81 1.4 Passwords.................................................................85 Password and user ID Restrictions and Considerations...............................86 -
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. -
*** Check Constraints - 10G
*** Check Constraints - 10g *** Create table and poulated with a column called FLAG that can only have a value of 1 or 2 SQL> CREATE TABLE check_const (id NUMBER, flag NUMBER CONSTRAINT check_flag CHECK (flag IN (1,2))); Table created. SQL> INSERT INTO check_const SELECT rownum, mod(rownum,2)+1 FROM dual CONNECT BY level <=10000; 10000 rows created. SQL> COMMIT; Commit complete. SQL> exec dbms_stats.gather_table_stats(ownname=>NULL, tabname=>'CHECK_CONST', estimate_percent=> NULL, method_opt=> 'FOR ALL COLUMNS SIZE 1'); PL/SQL procedure successfully completed. *** Now perform a search for a value of 3. There can be no such value as the Check constraint only permits values 1 or 2 ... *** The exection plan appears to suggest a FTS is being performed (remember, there are no indexes on the flag column) *** But the statistics clearly show no LIOs were performed, none SQL> SELECT * FROM check_const WHERE flag = 3; no rows selected Execution Plan ---------------------------------------------------------- Plan hash value: 1514750852 ---------------------------------------------------------------------------------- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time | ---------------------------------------------------------------------------------- | 0 | SELECT STATEMENT | | 1 | 6 | 0 (0)| | |* 1 | FILTER | | | | | | |* 2 | TABLE ACCESS FULL| CHECK_CONST | 1 | 6 | 6 (0)| 00:00:01 | ---------------------------------------------------------------------------------- Predicate Information (identified by operation id): --------------------------------------------------- -
Chapter 10. Declarative Constraints and Database Triggers
Chapter 10. Declarative Constraints and Database Triggers Table of contents • Objectives • Introduction • Context • Declarative constraints – The PRIMARY KEY constraint – The NOT NULL constraint – The UNIQUE constraint – The CHECK constraint ∗ Declaration of a basic CHECK constraint ∗ Complex CHECK constraints – The FOREIGN KEY constraint ∗ CASCADE ∗ SET NULL ∗ SET DEFAULT ∗ NO ACTION • Changing the definition of a table – Add a new column – Modify an existing column’s type – Modify an existing column’s constraint definition – Add a new constraint – Drop an existing constraint • Database triggers – Types of triggers ∗ Event ∗ Level ∗ Timing – Valid trigger types • Creating triggers – Statement-level trigger ∗ Option for the UPDATE event – Row-level triggers ∗ Option for the row-level triggers – Removing triggers – Using triggers to maintain referential integrity – Using triggers to maintain business rules • Additional features of Oracle – Stored procedures – Function and packages – Creating procedures – Creating functions 1 – Calling a procedure from within a function and vice versa • Discussion topics • Additional content and activities Objectives At the end of this chapter you should be able to: • Know how to capture a range of business rules and store them in a database using declarative constraints. • Describe the use of database triggers in providing an automatic response to the occurrence of specific database events. • Discuss the advantages and drawbacks of the use of database triggers in application development. • Explain how stored procedures can be used to implement processing logic at the database level. Introduction In parallel with this chapter, you should read Chapter 8 of Thomas Connolly and Carolyn Begg, “Database Systems A Practical Approach to Design, Imple- mentation, and Management”, (5th edn.). -
Clarion & ANSI SQL Standard Referential Integrity and Referential
Clarion & ANSI SQL Standard Referential Integrity and Referential Actions November 12, 2018 Whitemarsh Information Systems Corporation 2008 Althea Lane Bowie, Maryland 20716 Tele: 301-249-1142 Email: [email protected] Web: www.wiscorp.com Referential Integrity and Referential Actions Fundamental Definition: Actions resulting from instruction to the database engine created in the dictionary (i.e., schema) associated with “Relationship” specifications. For SQL-engine DBMSs, these relationship-specifications and actions relate to value congruence between the value-set of a primary key’s column(s) and the value-set of a Foreign key’s column(s). When either a Update or Delete action occurs that violates the value congruence, a Referential Action occurs. The actions depend on whether the Referential Action is specified. In ANSI SQL Standards, the four referential integrity actions: No Action, Cascade, or Set Null or Set Default. In Clarion, the five referential integrity actions are: None, Restrict, Cascade, Clear, Cascade Server, ClearServer and Restrict Server. Copyright 2018, Whitemarsh Information Systems Corporation Proprietary Data, All Rights Reserved 2 Referential Integrity and Referential Actions Referential Integrity and Actions Referential Action taken when violation occurs On Update On Delete Referential Action Parent Child Parent Child Function ANSI Clarion Table Table Table Table Parent Table No equivalent None: Instructs the Primary No change Row is Nothing. Primary Key Application Generator not key in the deleted Effect is to Column value can to generate any code to column foreign key make the change. Foreign maintain referential value can value child table Key Column value integrity between any change row an does not change. -
2.4. Constraints
PostgreSQL 7.3 Documentation Prev Chapter 2. Data Definition Next 2.4. Constraints Data types are a way to limit the kind of data that can be stored in a table. For many applications, however, the constraint they provide is too coarse. For example, a column containing a product price should probably only accept positive values. But there is no data type that accepts only positive numbers. Another issue is that you might want to constrain column data with respect to other columns or rows. For example, in a table containing product information, there should only be one row for each product number. To that end, SQL allows you to define constraints on columns and tables. Constraints give you as much control over the data in your tables as you wish. If a user attempts to store data in a column that would violate a constraint, an error is raised. This applies even if the value came from the default value definition. 2.4.1. Check Constraints A check constraint is the most generic constraint type. It allows you to specify that the value in a certain column must satisfy an arbitrary expression. For instance, to require positive product prices, you could use: CREATE TABLE products ( product_no integer, name text, price numeric CHECK (price > 0) ); As you see, the constraint definition comes after the data type, just like default value definitions. Default values and constraints can be listed in any order. A check constraint consists of the key word CHECK followed by an expression in parentheses. The check constraint expression should involve the column thus constrained, otherwise the constraint would not make too much sense. -
Reasoning Over Large Semantic Datasets
R O M A TRE UNIVERSITA` DEGLI STUDI DI ROMA TRE Dipartimento di Informatica e Automazione DIA Via della Vasca Navale, 79 – 00146 Roma, Italy Reasoning over Large Semantic Datasets 1 2 2 1 ROBERTO DE VIRGILIO ,GIORGIO ORSI ,LETIZIA TANCA , RICCARDO TORLONE RT-DIA-149 May 2009 1Dipartimento di Informatica e Automazione Universit`adi Roma Tre {devirgilio,torlone}@dia.uniroma3.it 2Dipartimento di Elettronica e Informazione Politecnico di Milano {orsi,tanca}@elet.polimi.it ABSTRACT This paper presents NYAYA, a flexible system for the management of Semantic-Web data which couples an efficient storage mechanism with advanced and up-to-date ontology reasoning capa- bilities. NYAYA is capable of processing large Semantic-Web datasets, expressed in a variety of formalisms, by transforming them into a collection of Semantic Data Kiosks that expose the native meta-data in a uniform fashion using Datalog±, a very general rule-based language. The kiosks form a Semantic Data Market where the data in each kiosk can be uniformly accessed using conjunctive queries and where users can specify user-defined constraints over the data. NYAYA is easily extensible and robust to updates of both data and meta-data in the kiosk. In particular, a new kiosk of the semantic data market can be easily built from a fresh Semantic- Web source expressed in whatsoever format by extracting its constraints and importing its data. In this way, the new content is promptly available to the users of the system. The approach has been experimented using well known benchmarks with very promising results. 2 1 Introduction Ever since Tim Berners Lee presented, in 2006, the design principles for Linked Open Data1, the public availability of Semantic-Web data has grown rapidly. -
Relational Schema Relational Integrity
Relational Schema Relational Integrity Unpassionate and purposeless Orlando never combine his incalculability! Infinitival Oswald signalize canonically or proceed trustingly when Piotr is leery. Orbadiah volatilizes her options bulgingly, she outwalks it amorally. Save my choice for tables can have no parent table, only on data are problems with multiple base tables may be a combination with the! Employee to radio mandatory role of Employee. DBMSs to check important data satisfies the semantics. Filing System, the dummy set add all Counties of all Countries. It does not seriously affect both tables related in relation schema designs the integrity constraints are. RFS, this sin that goes do dot use fresh unique ID to identify value object. Manual is separate horn the Product entity. Overlap constraints: Can Joe be an Hourly_Emps as through as a Contract_Emps entity? Web site which select a few attributes. Was this on helpful? It involves the relational tables that data are shown is an entity and implemented via objects are modified depending on file sharing services can! In relational schema may want to track of your session has gained wide range of moral character. There is our chance for duplication of data. An unknown error occurred. DBMSs but were originally slower. The second sentence to keep only two tables separated. Similarly, data manipulation, enabling them to shelter network traffic and unit run in disconnected mode. Eer object over any data item, delete all enrolled tuple. When there was not refundable and each table should not allowed through views reflects pdf solve mcq quiz yourself, relational integrity risk is called dno in. -
CSC 443 – Database Management Systems Data and Its Structure
CSC 443 – Database Management Systems Lecture 3 –The Relational Data Model Data and Its Structure • Data is actually stored as bits, but it is difficult to work with data at this level. • It is convenient to view data at different levels of abstraction . • Schema : Description of data at some abstraction level. Each level has its own schema. • We will be concerned with three schemas: physical , conceptual , and external . 1 Physical Data Level • Physical schema describes details of how data is stored: tracks, cylinders, indices etc. • Early applications worked at this level – explicitly dealt with details. • Problem: Routines were hard-coded to deal with physical representation. – Changes to data structure difficult to make. – Application code becomes complex since it must deal with details. – Rapid implementation of new features impossible. Conceptual Data Level • Hides details. – In the relational model, the conceptual schema presents data as a set of tables. • DBMS maps from conceptual to physical schema automatically. • Physical schema can be changed without changing application: – DBMS would change mapping from conceptual to physical transparently – This property is referred to as physical data independence 2 Conceptual Data Level (con’t) External Data Level • In the relational model, the external schema also presents data as a set of relations. • An external schema specifies a view of the data in terms of the conceptual level. It is tailored to the needs of a particular category of users. – Portions of stored data should not be seen by some users. • Students should not see their files in full. • Faculty should not see billing data. – Information that can be derived from stored data might be viewed as if it were stored. -
Data Base Lab the Microsoft SQL Server Management Studio Part-3
Data Base Lab Islamic University – Gaza Engineering Faculty Computer Department Lab -5- The Microsoft SQL Server Management Studio Part-3- By :Eng.Alaa I.Haniy. SQL Constraints Constraints are used to limit the type of data that can go into a table. Constraints can be specified when a table is created (with the CREATE TABLE statement) or after the table is created (with the ALTER TABLE statement). We will focus on the following constraints: NOT NULL UNIQUE PRIMARY KEY FOREIGN KEY CHECK DEFAULT Now we will describe each constraint in details. SQL NOT NULL Constraint By default, a table column can hold NULL values. The NOT NULL constraint enforces a column to NOT accept NULL values. The NOT NULL constraint enforces a field to always contain a value. This means that you cannot insert a new record, or update a record without adding a value to this field. The following SQL enforces the "PI_Id" column and the "LName" column to not accept NULL values CREATE TABLE Person ( PI_Id int NOT NULL, LName varchar(50) NOT NULL, FName varchar(50), Address varchar(50), City varchar(50) ) 2 SQL UNIQUE Constraint The UNIQUE constraint uniquely identifies each record in a database table. The UNIQUE and PRIMARY KEY constraints both provide a guarantee for uniqueness or a column or set of columns. A PRIMARY KEY constraint automatically has a UNIQUE constraint defined on it. Note that you can have many UNIQUE constraints per table, but only one PRIMARY KEY constraint per table. SQL UNIQUE Constraint on CREATE TABLE The following SQL creates a UNIQUE -
March 2017 Report
BCS THE CHARTERED INSTITUTE FOR IT BCS HIGHER EDUCATION QUALIFICATIONS BCS Level 6 Professional Graduate Diploma in IT ADVANCED DATABASE MANAGEMENT SYSTEMS March 2017 Answer any THREE questions out of FIVE. All questions carry equal marks. Time: THREE hours Answer any Section A questions you attempt in Answer Book A Answer any Section B questions you attempt in Answer Book B The marks given in brackets are indicative of the weight given to each part of the question. Calculators are NOT allowed in this examination. Section A Answer Section A questions in Answer Book A A1 Examiner's General Comments This was a fairly popular question, attempted by around half of the candidates, with two-thirds of the attempts achieving pass level marks. Therefore, the performance was generally quite good with a wide range of marks, some candidates producing near correct solutions. The definition of a true distributed database system is that it consists of a collection of geographically remote sites of physical databases, connected together via some kind of communication network, in which a user at any site can access data anywhere in the network exactly as if the data were all stored in one single database at the user’s own site. a) Explain the problems associated with achieving a true distributed database in practice. 12 marks ANSWER POINTER Fragmentation of tables requires maintenance of unique keys across horizontal fragments and consistency of primary keys that are reflected in vertical fragments. Also increased network traffic occurs as many fragments may need to be consulted to perform one query. -
(12) United States Patent (10) Patent No.: US 9,053,153 B2 Schreter (45) Date of Patent: Jun
US009053153B2 (12) United States Patent (10) Patent No.: US 9,053,153 B2 Schreter (45) Date of Patent: Jun. 9, 2015 (54) INTER-QUERY PARALLELIZATION OF 95. R. 358. RaSudevan al. et.....I707,as: al. CONSTRAINT CHECKING 7,113.953 B2 * 9/2006 Brown et al. ...... 707,615 7,240,054 B2 * 7/2007 Adiba et al. .......................... 1.1 (75) Inventor: Ivan Schreter, Malsch (DE) 8,301,934 B1 * 10/2012 Ramesh et al. ................. T14, 18 8,336,051 B2 * 12/2012 Gokulakannan ... ... 718, 101 (73) Assignee: SAP SE, Walldorf (DE) 8,375,047 B2 * 2/2013 Narayanan et al. ... 707 764 2002/01741.08 A1* 11/2002 Cotner et al. ..................... 707/3 - r 2004/0010502 A1* 1 2004 Bomfim et al. 7O7/1OO (*) Notice: Subject to any disclaimer, the term of this 2005, 0131893 A1* 6/2005 Von Glan .......................... 707/5 patent is extended or adjusted under 35 2006/0212465 A1* 9, 2006 Fish et al. ... 707/101 U.S.C. 154(b) by 12 days. 2007/0239661 A1* 10, 2007 Cattell et al. ...................... 707/2 2009/0037498 A1* 2/2009 Mukherjee et al. ........... 707,205 (21) Appl. No.: 13/525,935 2010/0005077 A1* 1/2010 Krishnamurthy et al. ........ 7O7/4 9 2011/0010330 A1 1/2011 McCline et al. .............. 707,602 1-1. 2012/0254887 A1* 10/2012 Rodriguez ... ... 718, 106 (22) Filed: Jun. 18, 2012 2012fO265728 A1* 10, 2012 Plattner et al. 707/6O7 2012/0278282 A1* 11/2012 Lu et al. ......... TO7/634 (65) Prior Publication Data 2012,0310985 A1* 12/2012 Gale et al.