Data Modelling and Databases. Exercise Session 7: Integrity Constraints
|
|
- Irene Norman
- 6 years ago
- Views:
Transcription
1 Data Modelling and Databases Exercise Session 7: Integrity Constraints 1
2 Database Design Textual Description Complete Design ER Diagram Relational Schema Conceptual Modeling Logical Modeling Physical Modeling SQL (DDL) Integrity Constraint 2
3 Integrity Constraints How can we define rules in a DB? 1. Attribute Constraints: intra-table rules 2. Referential Constraints: inter-table rules 3. Triggers: more complex rules Constraints are used to limit the type of data that can be inserted into a table. There exist two ways to specify constraints on a relation: When a table is created: CREATE TABLE After the table is created: ALTER TABLE 3
4 Integrity Constraints Name NOT NULL UNIQUE PRIMARY KEY FOREIGN KEY CHECK DEFAULT Description This enforces a field to always contain a value. This constraint uniquely identifies each record in a table. An attribute that is unique can be null. A primary key uniquely identifies each record in a table (= UNIQUE + NOT NULL), each table can have only one primary key. A foreign key is a reference that points from one table to the primary key of another table. It prevents actions that would destroy links between tables. [Referential Integrity Constraints] This constraint is used to limit the value range that can be placed in a column. CHECK can limit the values in certain columns based on values in other columns It is used to insert a default value into a column. The default value will be added to all new records, if no other value is specified. 4
5 Intra-Table Constraints Example: CREATE TABLE User ( id int(11) PRIMARY KEY, group varchar(10) DEFAULT guest', username varchar(20) UNIQUE, password varchar(30) NOT NULL, varchar(30) CHECK ( LIKE %@% ), ) CONSTRAINT chk_group CHECK group IN ( user, admin, guest ) ALTER TABLE User ADD CONSTRAINT uni_ UNIQUE ( ) Use CONSTRAINT statement to name your constraints (optional) 5
6 Referential Constraints A foreign key is a referential constraint between two tables. This is reference that points from one (or more) attribute(s) to the primary key of another table. A foreign key value must point to an existing tuple. If this is not the case, its value must be NULL, i.e. a FK value cannot point to a non-existing row! uid username 1 jribon 3 prtrem 4 lucasa cid uid comment 1 1 Hello World! 2 1 Students are smart. 3 2 I love DB!! 6
7 Inter-Table Constraints Example: CREATE TABLE User ( id int(11) PRIMARY KEY, group_id int(11) FOREIGN KEY (group_id) REFERENCES Group(id), username varchar(20), password varchar(30) ) CREATE TABLE Group ( id int(11) PRIMARY KEY, name varchar(10) ) 7
8 Referential Actions Referential actions ensure data integrity if a row (in a referenced table) is deleted or updated. This defines what should happens if we want to delete (or update) a row that is still referenced in another table. uid username 1 jribon 2 prtrem 3 lucasa? cid uid comment 1 1 Hello World! 2 1 Students are smart. 3 2 To be or not to be. Referenced Table Referencing Table 8
9 Referential Actions SQL-2003 specifies 5 different referential actions: Name CASCADE RESTRICT NO ACTION SET NULL SET DEFAULT Description The respective rows of the referencing table are deleted or updated together with the referenced row. A row cannot be deleted or updated as long as there is a reference to it from a referencing table. Integrity constraint is checked before executing the statement. [Pessimistic: expect violation] As RESTRICT, but integrity constraint is checked at the end of the UPDATE or DELETE statement. [Optimistic: assume no violation] The foreign key value (in the referencing row) is set to NULL when the referenced row is updated or deleted. Note: foreign key must be null-able. Similar to SET NULL, the foreign key is set to the column s default value when the referenced row is updated or deleted. 9
10 Inter-Table Constraints Example: CREATE TABLE User ( id int(11) PRIMARY KEY, group_id int(11), username varchar(20), password varchar(30) ) ALTER TABLE User ADD CONSTRAINT `fk_user2group` FOREIGN KEY (group_id) REFERENCES Group(id), ON DELETE RESTRICT ON UPDATE CASCADE; Foreign Key constraint with referential actions 10
11 Question 1.1 Which one does not allow NULL to be inserted? o UNIQUE o NOT NULL o FOREIGN KEY o PRIMARY KEY o CHECK 11
12 Question 1.1 Which one does not allow NULL to be inserted? o UNIQUE -> In SQL all NULLs are unique NOT NULL o FOREIGN KEY -> Allowed to be NULL PRIMARY KEY -> Can t be NULL CHECK -> Any NULL will cause it to fail 12
13 Question 1.2 True or False? 13
14 Question 1.2 True or False? 14
15 Question 2.1 Schema: Initial contents: What happens when we run the following queries? 15
16 Question 2.1 Schema: Initial contents: 16
17 Question 2.1 Schema: Initial contents: Allowed! Not allowed! id 2 already exists. 17
18 Question 2.1 Schema: Initial contents: 18
19 Question 2.1 Schema: Initial contents: Allowed! Allowed! 19
20 Question 2.1 Schema: Initial contents: 20
21 Question 2.1 Schema: Initial contents: Not allowed! ON DELETE NO ACTION Allowed! ON UPDATE SET NULL 21
22 Question 2.1 Schema: Initial contents: 22
23 Question 2.1 Schema: Initial contents: Allowed! ON DELETE CASCADE 23
24 Question 4 Which statements are true? 24
25 Question 4 Which statements are true? 25
26 Question 5 How can we add the following constraints to the schema? 1. The start date of salary has to be before the end date. 2. The end date in dept_emp table is either NULL (meaning sometime future) or is in the past. 3. One employee can only be the manager of one department at a time. This implies that the date entries in dept_manager table can not have overlaps for a certain employee. 26
27 Question 5 1. The start date of salary has to be before the end date. 27
28 Question 5 2. The end date in dept_emp table is either NULL (meaning sometime future) or is in the past. 28
29 Question 5 3. One employee can only be the manager of one department at a time. 29
EGCI 321: Database Systems. Dr. Tanasanee Phienthrakul
1 EGCI 321: Database Systems Dr. Tanasanee Phienthrakul 2 Chapter 10 Data Definition Language (DDL) 3 Basic SQL SQL language Considered one of the major reasons for the commercial success of relational
More informationAssignment 7: Integrity Constraints
Data Modelling and Databases Exercise dates: April 19, 2018 Ce Zhang, Gustavo Alonso Last update: April 19, 2018 Spring Semester 2018 Head TA: Ingo Müller Assignment 7: Integrity Constraints This assignment
More informationThe Relational Model. Relational Data Model Relational Query Language (DDL + DML) Integrity Constraints (IC)
The Relational Model Relational Data Model Relational Query Language (DDL + DML) Integrity Constraints (IC) Why Study the Relational Model? Most widely used model in Commercial DBMSs: Vendors: IBM, Microsoft,
More informationDATA AND SCHEMA MODIFICATIONS CHAPTERS 4,5 (6/E) CHAPTER 8 (5/E)
1 DATA AND SCHEMA MODIFICATIONS CHAPTERS 4,5 (6/E) CHAPTER 8 (5/E) 2 LECTURE OUTLINE Updating Databases Using SQL Specifying Constraints as Assertions and Actions as Triggers Schema Change Statements in
More informationWhere Are We? Next Few Lectures. Integrity Constraints Motivation. Constraints in E/R Diagrams. Keys in E/R Diagrams
Where Are We? Introduction to Data Management CSE 344 Lecture 15: Constraints We know quite a bit about using a DBMS Start with real-world problem, design ER diagram From ER diagram to relations -> conceptual
More informationChapter 1 SQL and Data
Chapter 1 SQL and Data What is SQL? Structured Query Language An industry-standard language used to access & manipulate data stored in a relational database E. F. Codd, 1970 s IBM 2 What is Oracle? A relational
More informationIntegrity Constraints (Reminder)
Constraints, Triggers and Active Databases Chapter 9 1 Integrity Constraints (Reminder) Key (relation): a list of attributes Primary key (Sql: PRIMARY KEY) Secondary key (UNIQUE) Foreign key (inter-relation):
More information1- a> [5pts] Create the new table by writing and executing a full SQL DDL statement based on the following schema:
1. [20pts] To track the history of financial information changes such as a driver s bank account, you are going to create a table to store the history of all bank account numbers. Once created, this table
More informationComp 5311 Database Management Systems. 4b. Structured Query Language 3
Comp 5311 Database Management Systems 4b. Structured Query Language 3 1 SQL as Data Definition Language Creates the Students relation. The type (domain) of each field is specified, and enforced by the
More informationLab # 2. Data Definition Language (DDL) Eng. Alaa O Shama
The Islamic University of Gaza Faculty of Engineering Department of Computer Engineering ECOM 4113: Database Lab Lab # 2 Data Definition Language (DDL) Eng. Alaa O Shama October, 2015 Objective To be familiar
More informationCSC 261/461 Database Systems Lecture 6. Fall 2017
CSC 261/461 Database Systems Lecture 6 Fall 2017 Use of WITH The WITH clause allows a user to define a table that will only be used in a particular query (not available in all SQL implementations) Used
More informationAsst. Prof. Lipyeow Lim Information & Computer Science Department University of Hawaii at Manoa
ICS 321 Spring 2011 Constraints, Triggers, Views & Indexes Asst. Prof. Lipyeow Lim Information & Computer Science Department University of Hawaii at Manoa 04/04/2011 Lipyeow Lim -- University of Hawaii
More informationIntroduction to Data Management. Lecture #4 (E-R Relational Translation)
Introduction to Data Management Lecture #4 (E-R Relational Translation) Instructor: Mike Carey mjcarey@ics.uci.edu Database Management Systems 3ed, R. Ramakrishnan and J. Gehrke 1 Announcements v Today
More informationData Modeling. Yanlei Diao UMass Amherst. Slides Courtesy of R. Ramakrishnan and J. Gehrke
Data Modeling Yanlei Diao UMass Amherst Slides Courtesy of R. Ramakrishnan and J. Gehrke 1 Outline v Conceptual Design: ER Model v Relational Model v Logical Design: from ER to Relational 2 Conceptual
More informationCSC 453 Database Technologies. Tanu Malik DePaul University
CSC 453 Database Technologies Tanu Malik DePaul University A Data Model A notation for describing data or information. Consists of mostly 3 parts: Structure of the data Data structures and relationships
More informationSQL: Part III. Announcements. Constraints. CPS 216 Advanced Database Systems
SQL: Part III CPS 216 Advanced Database Systems Announcements 2 Reminder: Homework #1 due in 12 days Reminder: reading assignment posted on Web Reminder: recitation session this Friday (January 31) on
More informationThe Relational Model Constraints and SQL DDL
The Relational Model Constraints and SQL DDL Week 2-3 Weeks 2-3 MIE253-Consens 1 Schedule Week Date Lecture Topic 1 Jan 9 Introduction to Data Management 2 Jan 16 The Relational Model 3 Jan. 23 Constraints
More informationSQL DATA DEFINITION LANGUAGE
SQL DATA DEFINITION LANGUAGE DATABASE SCHEMAS IN SQL SQL is primarily a query language, for getting information from a database. DML: Data Manipulation Language SFWR ENG 3DB3 FALL 2016 MICHAEL LIUT (LIUTM@MCMASTER.CA)
More informationThe Relational Model
The Relational Model UVic C SC 370, Fall 2002 Daniel M. German Department of Computer Science University of Victoria 3 1 The Relational Model CSC 370 dmgerman@uvic.ca Overview How is data represented in
More informationThe Relational Model of Data (ii)
ICS 321 Fall 2013 The Relational Model of Data (ii) Asst. Prof. Lipyeow Lim Information & Computer Science Department University of Hawaii at Manoa 1 Defining Relational Schema in SQL Two aspects: Data
More informationRelational Model. Topics. Relational Model. Why Study the Relational Model? Linda Wu (CMPT )
Topics Relational Model Linda Wu Relational model SQL language Integrity constraints ER to relational Views (CMPT 354 2004-2) Chapter 3 CMPT 354 2004-2 2 Why Study the Relational Model? Most widely used
More informationSQL DATA DEFINITION LANGUAGE
9/27/16 DATABASE SCHEMAS IN SQL SQL DATA DEFINITION LANGUAGE SQL is primarily a query language, for getting information from a database. SFWR ENG 3DB3 FALL 2016 But SQL also includes a data-definition
More informationdoc. RNDr. Tomáš Skopal, Ph.D. RNDr. Michal Kopecký, Ph.D.
course: Database Systems (NDBI025) SS2017/18 doc. RNDr. Tomáš Skopal, Ph.D. RNDr. Michal Kopecký, Ph.D. Department of Software Engineering, Faculty of Mathematics and Physics, Charles University in Prague
More informationDatabase Applications (15-415)
Database Applications (15-415) The Relational Model Lecture 3, January 18, 2015 Mohammad Hammoud Today Last Session: The entity relationship (ER) model Today s Session: ER model (Cont d): conceptual design
More informationCLASS DISCUSSION AND NOTES
Mon CLASS DISCUSSION AND NOTES October 2009 Tue Wed Thu Fri 19 20 21 22 23 AH-6; PBL & Project Peer Evaluations Chap. 7 SQL/DB Construction AH-6; PBL & Project Peer Evaluations Chap. 7 SQL/DB Construction
More informationLab # 4. Data Definition Language (DDL)
Islamic University of Gaza Faculty of Engineering Department of Computer Engineering ECOM 4113: Lab # 4 Data Definition Language (DDL) Eng. Haneen El-Masry November, 2014 2 Objective To be familiar with
More informationSQL Server. Lecture3 Cascading referential integrity constraint
SQL Server Lecture3 Cascading referential integrity constraint insert into tblperson values (4,'May','Ma@m.com',4) Msg 547, Level 16, State 0, Line 1 The INSERT statement conflicted with the FOREIGN KEY
More informationThe Relational Model
The Relational Model UVic C SC 370, Fall 2002 Daniel M. German Department of Computer Science University of Victoria September 25, 2002 Version: 1.03 3 1 The Relational Model (1.03) CSC 370 dmgerman@uvic.ca
More informationStructure Query Language (SQL)
Structure Query Language (SQL) 1 6.12.2 OR operator OR operator is also used to combine multiple conditions with Where clause. The only difference between AND and OR is their behavior. When we use AND
More informationThe Relational Model. Why Study the Relational Model? Relational Database: Definitions
The Relational Model Database Management Systems, R. Ramakrishnan and J. Gehrke 1 Why Study the Relational Model? Most widely used model. Vendors: IBM, Microsoft, Oracle, Sybase, etc. Legacy systems in
More informationIntroduction to Data Management. Lecture #4 (E-R à Relational Design)
Introduction to Data Management Lecture #4 (E-R à Relational Design) Instructor: Mike Carey mjcarey@ics.uci.edu Database Management Systems 3ed, R. Ramakrishnan and J. Gehrke 1 Announcements v Reminders:
More informationSQL: Data De ni on. B0B36DBS, BD6B36DBS: Database Systems. h p://www.ksi.m.cuni.cz/~svoboda/courses/172-b0b36dbs/ Lecture 3
B0B36DBS, BD6B36DBS: Database Systems h p://www.ksi.m.cuni.cz/~svoboda/courses/172-b0b36dbs/ Lecture 3 SQL: Data De ni on Mar n Svoboda mar n.svoboda@fel.cvut.cz 13. 3. 2018 Czech Technical University
More informationIntroduction to Database Systems CSE 414
Introduction to Database Systems CSE 414 Lecture 16: Constraints CSE 414 - Spring 2015 1 Announcements Reminders: Web quiz due Monday night XML homework due Wednesday night Today: Constraints (7.1, 7.2,
More informationRelational data model
Relational data model Iztok Savnik FAMNIT, 18/19 Why Study the Relational Model? Most widely used model. Vendors: IBM, Informix, Microsoft, Oracle, Sybase, etc. Legacy systems in older models E.G., IBM
More informationThe Relational Model
The Relational Model What is the Relational Model Relations Domain Constraints SQL Integrity Constraints Translating an ER diagram to the Relational Model and SQL Views A relational database consists
More informationOverview. Data Integrity. Three basic types of data integrity. Integrity implementation and enforcement. Database constraints Transaction Trigger
Data Integrity IT 4153 Advanced Database J.G. Zheng Spring 2012 Overview Three basic types of data integrity Integrity implementation and enforcement Database constraints Transaction Trigger 2 1 Data Integrity
More informationITCS 3160 DATA BASE DESIGN AND IMPLEMENTATION
ITCS 3160 DATA BASE DESIGN AND IMPLEMENTATION JING YANG 2010 FALL Class 3: The Relational Data Model and Relational Database Constraints Outline 2 The Relational Data Model and Relational Database Constraints
More informationOracle Create Table Foreign Key On Delete No
Oracle Create Table Foreign Key On Delete No Action Can I create a foreign key against only part of a composite primary key? For example, if you delete a row from the ProductSubcategory table, it could
More informationCOGS 121 HCI Programming Studio. Week 03 - Tech Lecture
COGS 121 HCI Programming Studio Week 03 - Tech Lecture Housekeeping Assignment #1 extended to Monday night 11:59pm Assignment #2 to be released on Tuesday during lecture Database Management Systems and
More informationSQL DATA DEFINITION: KEY CONSTRAINTS. CS121: Relational Databases Fall 2017 Lecture 7
SQL DATA DEFINITION: KEY CONSTRAINTS CS121: Relational Databases Fall 2017 Lecture 7 Data Definition 2 Covered most of SQL data manipulation operations Continue exploration of SQL data definition features
More informationSQL: A COMMERCIAL DATABASE LANGUAGE. Data Change Statements,
SQL: A COMMERCIAL DATABASE LANGUAGE Data Change Statements, Outline 1. Introduction 2. Data Definition, Basic Constraints, and Schema Changes 3. Basic Queries 4. More complex Queries 5. Aggregate Functions
More informationCOSC344 Database Theory and Applications. σ a= c (P) Lecture 3 The Relational Data. Model. π A, COSC344 Lecture 3 1
COSC344 Database Theory and Applications σ a= c (P) S P Lecture 3 The Relational Data π A, C (H) Model COSC344 Lecture 3 1 Overview Last Lecture Database design ER modelling This Lecture Relational model
More informationThe DBMS accepts requests for data from the application program and instructs the operating system to transfer the appropriate data.
Managing Data Data storage tool must provide the following features: Data definition (data structuring) Data entry (to add new data) Data editing (to change existing data) Querying (a means of extracting
More informationThe Relational Model. Chapter 3. Comp 521 Files and Databases Fall
The Relational Model Chapter 3 Comp 521 Files and Databases Fall 2012 1 Why Study the Relational Model? Most widely used model by industry. IBM, Informix, Microsoft, Oracle, Sybase, etc. It is simple,
More informationSQL DATA DEFINITION LANGUAGE
SQL DATA DEFINITION LANGUAGE DATABASE SCHEMAS IN SQL SQL is primarily a query language, for getting information from a database. DML: Data Manipulation Language SFWR ENG 3DB3 FALL 2016 MICHAEL LIUT (LIUTM@MCMASTER.CA)
More informationThe Relational Model. Chapter 3
The Relational Model Chapter 3 Why Study the Relational Model? Most widely used model. Systems: IBM DB2, Informix, Microsoft (Access and SQL Server), Oracle, Sybase, MySQL, etc. Legacy systems in older
More informationIntroduction to Data Management. Lecture #5 Relational Model (Cont.) & E-Rà Relational Mapping
Introduction to Data Management Lecture #5 Relational Model (Cont.) & E-Rà Relational Mapping Instructor: Mike Carey mjcarey@ics.uci.edu Database Management Systems 3ed, R. Ramakrishnan and J. Gehrke 1
More informationCSE 530A. ER Model to Relational Schema. Washington University Fall 2013
CSE 530A ER Model to Relational Schema Washington University Fall 2013 Relational Model A relational database consists of a group of relations (a.k.a., tables) A relation (table) is a set of tuples (rows)
More informationThe Relational Model. Chapter 3. Database Management Systems, R. Ramakrishnan and J. Gehrke 1
The Relational Model Chapter 3 Database Management Systems, R. Ramakrishnan and J. Gehrke 1 Why Study the Relational Model? Most widely used model. Vendors: IBM, Informix, Microsoft, Oracle, Sybase, etc.
More informationAnnouncements (September 18) SQL: Part II. Solution 1. Incomplete information. Solution 3? Solution 2. Homework #1 due today (11:59pm)
Announcements (September 18) 2 SQL: Part II Homework #1 due today (11:59pm) Submit in class, slide underneath my office door Sample solution available Thursday Homework #2 assigned today CPS 116 Introduction
More information3.1. Keys: Super Key, Candidate Key, Primary Key, Alternate Key, Foreign Key
Unit 3: Types of Keys & Data Integrity 3.1. Keys: Super Key, Candidate Key, Primary Key, Alternate Key, Foreign Key Different Types of SQL Keys A key is a single or combination of multiple fields in a
More informationLAB 3 Notes. Codd proposed the relational model in 70 Main advantage of Relational Model : Simple representation (relationstables(row,
LAB 3 Notes The Relational Model Chapter 3 In the previous lab we discussed the Conceptual Database Design Phase and the ER Diagram. Today we will mainly discuss how to convert an ER model into the Relational
More informationIntroduction to Data Management CSE 344
Introduction to Data Management CSE 344 Lecture 16: Constraints CSE 344 - Fall 2014 1 Announcements Sections tomorrow: XML. Quiz and next HW on XML posted soon, due next week after midterm HW 4 due tomorrow
More informationChapter 4. Basic SQL. Copyright 2011 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
Chapter 4 Basic SQL Copyright 2011 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Chapter 4 Outline SQL Data Definition and Data Types Specifying Constraints in SQL Basic Retrieval Queries
More informationThe Relational Model 2. Week 3
The Relational Model 2 Week 3 1 We have seen how to create a database schema, how do we create an actual database on our computers? professor(pid : string, name : string) course(pid : string, number :
More informationSQL language. Jaroslav Porubän, Miroslav Biňas, Milan Nosáľ (c)
SQL language Jaroslav Porubän, Miroslav Biňas, Milan Nosáľ (c) 2011-2016 SQL - Structured Query Language SQL is a computer language for communicating with DBSM Nonprocedural (declarative) language What
More informationSQL: Data Definition Language. csc343, Introduction to Databases Diane Horton Fall 2017
SQL: Data Definition Language csc343, Introduction to Databases Diane Horton Fall 2017 Types Table attributes have types When creating a table, you must define the type of each attribute. Analogous to
More informationRelational Database Systems Part 01. Karine Reis Ferreira
Relational Database Systems Part 01 Karine Reis Ferreira karine@dpi.inpe.br Aula da disciplina Computação Aplicada I (CAP 241) 2016 Database System Database: is a collection of related data. represents
More informationChapter 4. Basic SQL. SQL Data Definition and Data Types. Basic SQL. SQL language SQL. Terminology: CREATE statement
Chapter 4 Basic SQL Basic SQL SQL language Considered one of the major reasons for the commercial success of relational databases SQL Structured Query Language Statements for data definitions, queries,
More informationRelational Model History. COSC 416 NoSQL Databases. Relational Model (Review) Relation Example. Relational Model Definitions. Relational Integrity
COSC 416 NoSQL Databases Relational Model (Review) Dr. Ramon Lawrence University of British Columbia Okanagan ramon.lawrence@ubc.ca Relational Model History The relational model was proposed by E. F. Codd
More informationDatabase Management System Dr. S. Srinath Department of Computer Science & Engineering Indian Institute of Technology, Madras Lecture No.
Database Management System Dr. S. Srinath Department of Computer Science & Engineering Indian Institute of Technology, Madras Lecture No. # 5 Structured Query Language Hello and greetings. In the ongoing
More informationConstraints. Primary Key Foreign Key General table constraints Domain constraints Assertions Triggers. John Edgar 2
CMPT 354 Constraints Primary Key Foreign Key General table constraints Domain constraints Assertions Triggers John Edgar 2 firstname type balance city customerid lastname accnumber rate branchname phone
More informationUsing a DBMS. Shan-Hung Wu & DataLab CS, NTHU
Using a DBMS Shan-Hung Wu & DataLab CS, NTHU DBMS Database A database is a collection of your data stored in a computer A DBMS (DataBase Management System) is a software that manages databases 2 Outline
More informationChapter 1: Introduction
Chapter 1: Introduction Chapter 2: Intro. To the Relational Model Database System Concepts, 6 th Ed. See www.db-book.com for conditions on re-use Database Management System (DBMS) DBMS is Collection of
More informationdownload instant at The Relational Data Model
3 The Relational Data Model EXERCISES 3.1 Define data atomicity as it relates to the definition of relational databases. Contrast data atomicity with transaction atomicity as used in a transaction processing
More informationDatabase Management System Dr. S. Srinath Department of Computer Science & Engineering Indian Institute of Technology, Madras Lecture No.
Database Management System Dr. S. Srinath Department of Computer Science & Engineering Indian Institute of Technology, Madras Lecture No. # 13 Constraints & Triggers Hello and welcome to another session
More informationCONSTRAINTS AND UPDATES CHAPTER 3 (6/E) CHAPTER 5 (5/E)
1 CONSTRAINTS AND UPDATES CHAPTER 3 (6/E) CHAPTER 5 (5/E) 3 LECTURE OUTLINE Constraints in Relational Databases Update Operations 4 SATISFYING INTEGRITY CONSTRAINTS Constraints are restrictions on the
More informationCOSC 304 Introduction to Database Systems SQL DDL. Dr. Ramon Lawrence University of British Columbia Okanagan
COSC 304 Introduction to Database Systems SQL DDL Dr. Ramon Lawrence University of British Columbia Okanagan ramon.lawrence@ubc.ca SQL Overview Structured Query Language or SQL is the standard query language
More informationThe Relational Model. Week 2
The Relational Model Week 2 1 Relations A relation is a more concrete construction, of something we have seen before, the ER diagram. name S.S.N students street city A relation is (just!) a table! We will
More informationModule 9: Managing Schema Objects
Module 9: Managing Schema Objects Overview Naming guidelines for identifiers in schema object definitions Storage and structure of schema objects Implementing data integrity using constraints Implementing
More informationSQL: Concepts. Todd Bacastow IST 210: Organization of Data 2/17/ IST 210
SQL: Concepts Todd Bacastow IST 210: Organization of Data 2/17/2004 1 Design questions How many entities are there? What are the major entities? What are the attributes of each entity? Is there a unique
More informationThe Relational Model. Chapter 3. Comp 521 Files and Databases Fall
The Relational Model Chapter 3 Comp 521 Files and Databases Fall 2014 1 Why the Relational Model? Most widely used model by industry. IBM, Informix, Microsoft, Oracle, Sybase, MySQL, Postgres, Sqlite,
More informationCOSC344 Database Theory and Applications. Lecture 5 SQL - Data Definition Language. COSC344 Lecture 5 1
COSC344 Database Theory and Applications Lecture 5 SQL - Data Definition Language COSC344 Lecture 5 1 Overview Last Lecture Relational algebra This Lecture Relational algebra (continued) SQL - DDL CREATE
More informationIntroduction to Data Management CSE 344
Introduction to Data Management CSE 344 Lecture 16: Constraints CSE 344 - Winter 2014 1 Announcements WQ5 due tonight deadline extended only for this WQ HW4 due tomorrow HW 5 posted, due next Thursday
More informationDatabase Management Systems. Chapter 3 Part 1
Database Management Systems Chapter 3 Part 1 The Relational Model Database Management Systems 3ed, R. Ramakrishnan and J. Gehrke 1 Why Study the Relational Model? Most widely used model. Vendors: IBM,
More informationDatabases. Jörg Endrullis. VU University Amsterdam
Databases Jörg Endrullis VU University Amsterdam The Relational Model Overview 1. Relational Model Concepts: Schema, State 2. Null Values 3. Constraints: General Remarks 4. Key Constraints 5. Foreign Key
More informationIntermediate SQL ( )
CSL 451 Introduction to Database Systems Intermediate SQL (4.1-4.4) Department of Computer Science and Engineering Indian Institute of Technology Ropar Narayanan (CK) Chatapuram Krishnan! Summary Join
More informationLet s briefly review important EER inheritance concepts
Let s briefly review important EER inheritance concepts 1 is-a relationship Copyright (c) 2011 Pearson Education 2 Basic Constraints Partial / Disjoint: Single line / d in circle Each entity can be an
More informationThe Relational Data Model and Relational Database Constraints
CHAPTER 5 The Relational Data Model and Relational Database Constraints Copyright 2017 Ramez Elmasri and Shamkant B. Navathe Slide 1-2 Chapter Outline Relational Model Concepts Relational Model Constraints
More informationSQL: Part II. Announcements (September 18) Incomplete information. CPS 116 Introduction to Database Systems. Homework #1 due today (11:59pm)
SQL: Part II CPS 116 Introduction to Database Systems Announcements (September 18) 2 Homework #1 due today (11:59pm) Submit in class, slide underneath my office door Sample solution available Thursday
More informationChapter 7 Constraints and Triggers. Spring 2011 Instructor: Hassan Khosravi
Chapter 7 Constraints and Triggers Spring 2011 Instructor: Hassan Khosravi SQL: Constraints and Triggers Certain properties we d like our database to hold Modification of the database may break these properties
More informationIntroduction to SQL Server. nikos bikakis
Introduction to SQL Server nikos bikakis bikakis@dblab.ntua.gr dblab NTU Athens Dec 2011 Introduction MS SQL Server Database server Product of Microsoft Relational DB From: 1989 (SQL Server 1.0) To: July
More informationOracle Database 10g Express
Oracle Database 10g Express This tutorial prepares the Oracle Database 10g Express Edition Developer to perform common development and administrative tasks of Oracle Database 10g Express Edition. Objectives
More informationThe Relational Model. Outline. Why Study the Relational Model? Faloutsos SCS object-relational model
The Relational Model CMU SCS 15-415 C. Faloutsos Lecture #3 R & G, Chap. 3 Outline Introduction Integrity constraints (IC) Enforcing IC Querying Relational Data ER to tables Intro to Views Destroying/altering
More informationData Manipulation (DML) and Data Definition (DDL)
Data Manipulation (DML) and Data Definition (DDL) 114 SQL-DML Inserting Tuples INSERT INTO REGION VALUES (6,'Antarctica','') INSERT INTO NATION (N_NATIONKEY, N_NAME, N_REGIONKEY) SELECT NATIONKEY, NAME,
More informationThe Basic (Flat) Relational Model. Copyright 2011 Pearson Education, Inc. Publishing as Pearson Addison-Wesley
The Basic (Flat) Relational Model Copyright 2011 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Chapter 3 Outline The Relational Data Model and Relational Database Constraints Relational
More informationTechno India Batanagar Computer Science and Engineering. Model Questions. Subject Name: Database Management System Subject Code: CS 601
Techno India Batanagar Computer Science and Engineering Model Questions Subject Name: Database Management System Subject Code: CS 601 Multiple Choice Type Questions 1. Data structure or the data stored
More informationDatabase Management System (15ECSC208) UNIT I: Chapter 2: Relational Data Model and Relational Algebra
Database Management System (15ECSC208) UNIT I: Chapter 2: Relational Data Model and Relational Algebra Relational Data Model and Relational Constraints Part 1 A simplified diagram to illustrate the main
More informationSQL: A COMMERCIAL DATABASE LANGUAGE. Complex Constraints
SQL: A COMMERCIAL DATABASE LANGUAGE Complex Constraints Outline 1. Introduction 2. Data Definition, Basic Constraints, and Schema Changes 3. Basic Queries 4. More complex Queries 5. Aggregate Functions
More informationBasic SQL. Basic SQL. Basic SQL
Basic SQL Dr Fawaz Alarfaj Al Imam Mohammed Ibn Saud Islamic University ACKNOWLEDGEMENT Slides are adopted from: Elmasri & Navathe, Fundamentals of Database Systems MySQL Documentation Basic SQL Structured
More informationCS W Introduction to Databases Spring Computer Science Department Columbia University
CS W4111.001 Introduction to Databases Spring 2018 Computer Science Department Columbia University 1 in SQL 1. Key constraints (PRIMARY KEY and UNIQUE) 2. Referential integrity constraints (FOREIGN KEY
More informationLecture7: SQL Overview, Oracle Data Type, DDL and Constraints Part #2
IS220 : Database Fundamentals College of Computer and Information Sciences - Information Systems Dept. Lecture7: SQL Overview, Oracle Data Type, DDL and Constraints Part #2 Ref. Chapter6 Prepared by L.
More informationFull file at
SQL for SQL Server 1 True/False Questions Chapter 2 Creating Tables and Indexes 1. In order to create a table, three pieces of information must be determined: (1) the table name, (2) the column names,
More informationDB Creation with SQL DDL
DB Creation with SQL DDL Outline SQL Concepts Data Types Schema/Table/View Creation Transactions and Access Control Objectives of SQL Ideally, database language should allow user to: create the database
More informationRelational model continued. Understanding how to use the relational model. Summary of board example: with Copies as weak entity
COS 597A: Principles of Database and Information Systems Relational model continued Understanding how to use the relational model 1 with as weak entity folded into folded into branches: (br_, librarian,
More informationRelational Data Model. Christopher Simpkins
Relational Data Model Christopher Simpkins 1 / 22 Relational Data Model A relation schema R(A a,..., A n ) is a relation name R and a list of attributes A 1,..., A n. Each attribute A i is the name of
More informationRelational Model, Key Constraints
Relational Model, Key Constraints PDBM 6.1 Dr. Chris Mayfield Department of Computer Science James Madison University Jan 23, 2019 What is a data model? Notation for describing data or information Structure
More informationIn This Lecture. SQL Data Definition SQL SQL. Non-Procedural Programming. Notes. Database Systems Lecture 5 Natasha Alechina
This Lecture Database Systems Lecture 5 Natasha Alechina The language, the relational model, and E/R diagrams CREATE TABLE Columns Primary Keys Foreign Keys For more information Connolly and Begg chapter
More informationSQL: Data Definition Language
SQL: Data Definition Language CSC 343 Winter 2018 MICHAEL LIUT (MICHAEL.LIUT@UTORONTO.CA) DEPARTMENT OF MATHEMATICAL AND COMPUTATIONAL SCIENCES UNIVERSITY OF TORONTO MISSISSAUGA Database Schemas in SQL
More informationINTRODUCTION TO RELATIONAL DATABASE SYSTEMS
INTRODUCTION TO RELATIONAL DATABASE SYSTEMS DATENBANKSYSTEME 1 (INF 3131) Torsten Grust Universität Tübingen Winter 2017/18 1 CONSTRAINTS Recall the recent correlated SQL query returning the LEGO bricks
More information