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Oracle: A Relational Database System (RDBMS)

Vandana Janeja

10th February 2004

For : Database Systems22:198:603

Prof. Vijay Atluri

Adapted from material by Dr.Richard Holowczak and Dr.Soon Chun

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Outline

Background SQL*PLUS SQL

DDL DML DCL Examples

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Components

Other details at: http://cimic.rutgers.edu/~holowcza/present/oracle97/index.htm

Front end application

VB, Access, Excel etc.

ODBC DriverOracle SybaseAccess

Oracle Server

SybaseServer

Access DB

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Core Database Engine

ORACLE RDBMS (Oracle Universal server) Integrated Data Dictionary: manage tables owned

by all users in a system SQL: language to access and manipulate data PL/SQL: a procedural extension to SQL language

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Interface Tools to access data

SQL*Plus: a command line interface Developer (Developer/2000): forms, reports,

and graphical interfaces

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Connectivity

SQL*Net and Net8: allow a Oracle client machine to communicate with Oracle data server

SQL*Connect and Oracle Gateways: communicate a client machine to access non-oracle data on server machine

Oracle Server: receives requests from client machines and submits them to Oracle RDBMS

Oracle ODBC drivers: connect software to Oracle databases

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SQL*Plus

Command line tool that process user’s SQL statements

Requires Oracle account

SQLDDL

DML

DCL

Data Definition

Data Manipulation

Data Control

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Same as your pegasus password

Password: MBAgrad2004

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Changing SQL*Plus password

passw command

Getting help

Help command

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SQL*Plus Commands

Example of SQL stmt: select * from tab; describe <table name> list : list current sql stmt edit : edit current sql statement (or ! Editorname <filename>) where editor

name is vi or pico input : add one or more lines to sqlplus buffer spool : start directing output of sql statements to a file spool off : turn the spool off run (or /): execute the statement in the current buffer save <filename.sql> : save current sql stmt to a file get <filename.sql> : load sql statements into buffer spool <filename>: send output from sql stmt to a file start <filename.sql>: load script file with sql stmts and run them help quit

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Typing a SQL command

Editing SQL command in a file

Saving SQL command in a file

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Executing the SQL command in a file

vi Editor

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Editing SQL command in a notepad

Copy and paste the command

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Basic vi primerFor more - “man vi”

Esc key to toggle between edit and insert mode <- -> down-arrow up-arrow arrow keys move the

cursor h j k l same as arrow keys x delete a character dw delete a word dd delete a line 3dd delete 3 lines u undo previous change ZZ exit vi, saving changes :q!CR quit, discarding changes :wq write and save changes

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Structured Query Language (SQL)

The standard query language for creating and manipulating and controlling data in relational databases

MS Access, Oracle, Sybase, Informix, etc. specified by a command-line tool or is embedded into a general purpose programming language, C, Pascal,

Java, Perl...

Data Definition Language (DDL) Used to create (define) data structures such as tables, indexes, clusters

Data Manipulation Language (DML) is used to store, retrieve and update data from tables

Data Control Language used to control the access to the database objects created using DDL and DML

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SQL as Data Definition Language

DDL is used to define the schema of the database (a collection of database objects, e.g. tables, views, indexes, sequences). Create, Drop or Alter a table Create or Drop an Index Define Integrity constraints Define access privileges to users Define access privileges on objects

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Create Table

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Create, modify, drop Tables, views, and sequences

CREATE TABLE employee

( emp_number char(4), fname VARCHAR2(8), minit VARCHAR2(2), lname VARCHAR2(9), ssn VARCHAR2(9) NOT NULL, bdate DATE, address VARCHAR2(27), sex VARCHAR2(1), salary NUMBER(7) NOT NULL, superssn VARCHAR2(9), dno NUMBER(1) NOT NULL,

PRIMARY KEY (emp_number)) ;CREATE TABLE dependant (

Last_Name d_last_name NOT NULL,

First_name VARCHAR(18) NOT NULL,

Soc_Sec d_soc_sec NOT NULL,

Date_of_Birth DATE,

Employee_Soc_Sec d_soc_sec NOT NULL );

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Data Types

A table is made up of one or more columns Each column is given a name and a data type that

reflects the kind of data it will store. Oracle supports four basic data types

CHAR NUMBER DATE RAW. There are also a few additional variations on the RAW and

CHAR data types.

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VARCHAR2 Character data type. Can contain letters, numbers and punctuation. The syntax : VARCHAR2(size) where size is the maximum

number of alphanumeric characters the column can hold. In Oracle8, the maximum size of a VARCHAR2 column is

4,000 bytes.

NUMBER Numeric data type. Can contain integer or floating point numbers only. The syntax : NUMBER(precision, scale) where precision is

the total size of the number including decimal point and scale is the number of places to the right of the decimal.

For example, NUMBER(6,2) can hold a number between -999.99 and 999.99.

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DATE – Date and Time data type. Can contain a date and time portion in the format: DD-MON-YY HH:MI:SS. No additional information needed when specifying the DATE data type. the time of 00:00:00 is used as a default. The output format of the date and time can be modified

RAW – Free form binary data. Can contain binary data up to 255 characters. Data type LONG RAW can contain up to 2 gigabytes of binary data. RAW and LONG RAW data cannot be indexed and can not be displayed or

queried in SQL*Plus. Only one RAW column is allowed per table.

LOB – Large Object data types. These include BLOB (Binary Large OBject) and CLOB (Character Large

OBject). More than one LOB column can appear in a table. These data types are the prefferred method for storing large objects such as text

documents (CLOB), images, or video (BLOB).

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Foreign Key

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Primary key

CREATE TABLE order_header ( order_number NUMBER(10,0) NOT NULL, order_date DATE, sales_person VARCHAR(25), bill_to VARCHAR(35), bill_to_address VARCHAR(45), bill_to_city VARCHAR(20), bill_to_state VARCHAR(2), bill_to_zip VARCHAR(10), PRIMARY KEY (order_number) );

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Foreign key

CREATE TABLE order_items (

order_number NUMBER(10,0) NOT NULL,

line_item NUMBER(4,0) NOT NULL,

part_number VARCHAR(12) NOT NULL,

quantity NUMBER(4,0),

PRIMARY KEY (order_number, line_item),

FORIEGN KEY (order_number)

REFERENCES order_header (order_number),

FOREIGN KEY (part_number)

REFERENCES parts (part_number) );

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Creating indexes/views/sequences

CREATE INDEX items_index ON order_items (order_number, line_item) ASC ;

drop index index_name create view emp_dno1 as select fname, lname, deptno from emp where

deptno=4001

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Example : Create/ Drop Table

CREATE TABLE emp_department_1 AS SELECT fname, minit, lname, bdate FROM employee WHERE dno = 1 ;

create table high_pay_emp as

select * from employee where salary > 50000

Drop table <table_name> Drop table high_pay_emp

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Other Constraints

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Specifying Constraints on Columns and Tables

Constraints on attributes: NOT NULL - Attribute may not take a NULL value

DEFAULT - Store a given default value i PRIMARY KEY - Indicate which attribute(s) form the primary key

FOREIGN KEY - Indicate which attribute(s) form a foreign key.

UNIQUE - Indicates which attribute(s) must have unique values.

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Referential Integrity Constraint

Specify the behavior for child tuples when a parent tuple is modified.

Action to take if referential integrity is violated: SET NULL - Child tuples foreign key is set to NULL - Orphans.

SET DEFAULT - Set the value of the foreign key to some default value.

CASCADE - Child tuples are updated (or deleted) according to the action take on the parent tuple.

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Example

CREATE TABLE order_items ( order_number NUMBER(10,0) NOT NULL, line_item NUMBER(4,0) NOT NULL, part_number VARCHAR(12) NOT NULL, quantity NUMBER(4,0), PRIMARY KEY (order_number, line_item), FORIEGN KEY (order_number) REFERENCES order_header (order_number) ON DELETE SET DEFAULT ON UPDATE CASCADE, FOREIGN KEY (part_number) REFERENCES parts (part_number));

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Constraints with name

CREATE TABLE order_header (

order_number NUMBER(10,0) NOT NULL,

order_date DATE,

sales_person VARCHAR(25),

bill_to VARCHAR(35),

bill_to_address VARCHAR(45),

bill_to_city VARCHAR(20),

bill_to_state VARCHAR(2),

bill_to_zip VARCHAR(10),

CONSTRAINT order_header_pk

PRIMARY KEY (order_number) );

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Drop

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Removing Schema Components with DROP

DROP TABLE table_name

DROP TABLE table_name CASCADE

DROP TABLE table_name RESTRICT

DROP INDEX index_name

DROP CONSTRAINT table_name.constraint_name

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Alter

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Given a table - students

CREATE TABLE student (studentid NUMBER(5,0), first_name VARCHAR2(25),last_name Varchar2(10),

major VARCHAR2(15), gpa NUMBER(6,3) default 4.0, tutorid NUMBER(5,0), home_phone varchar2(10));

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Changing Table Components with ALTER

Changing Attributes:ALTER TABLE student MODIFY last_name VARCHAR(35);

alter table student modify gpa NUMBER(6,3) default 0.0;

Adding Attributes:ALTER TABLE student ADD admission DATE;

Removing Attributes (not widely implemented):ALTER TABLE student DROP column home_phone

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Syntax of commands

alter table … add/modify …column create table tname ( colname, datatype, not null, ...); create table .. as <sql stmt> drop table tname create index <indexname> on tname (colname, colname); drop index <indexname> create sequence <seqname> increament by .. start with …maxvalue …

cycle; drop sequence create view <vname> as <sql select stment = select <colnames>

from tname where <condition> (read only, no insert, update or delete) drop view

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DML

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SQL DML

commit delete insert rollback select update

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Data Manipulation Language

INSERT INTO tablename (column1, column2, ... columnX)

VALUES (val1, val2, ... valX);

Examples: INSERT INTO employee (first_name, last_name, street, city, state, zip) VALUES ("Buddy", "Rich", "123 Sticks Ln.", "Fillville", "TN", "31212");

INSERT INTO stocks (symbol, close_date, close_price) VALUES ("IBM", "03-JUN-94", 104.25);

INSERT INTO student_grades (student_id, test_name, score, grade) VALUES (101, "Quiz 1", 88, "B+");

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Delete and Update commands

DELETE FROM <table name> WHERE <where-clause> If the WHERE clause is omitted, all rows in the table

will be deleted. UPDATE <table name> SET<column

name> = <expression> WHERE <where-clause> UPDATE employee SET salary = salary * 1.03

WHERE dno = (SELECT dno FROM department WHERE dname = 'MARKETING');

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DCL: Data Control Language

Controlling Access to database objects such as tables and views

Example : Granting “Mary” the access to Table “student” (for inserting, updating and deleting)

GRANT INSERT, UPDATE, DELETE ON Student TO Mary GRANT <privileges> ON <object name>

     TO <grantee> [ <comma> <grantee> ... ]        [ WITH GRANT OPTION ]

WITH GRANT OPTION: allows the grantee to further grant privileges Can be limited to a column of a table, Ex: GRANT UPDATE(name) ON

Student TO Mary To revoke privileges : REVOKE

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A Bank Example

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Designing A Database - A Bank Example

A database to track their customers and accounts. Tables

CUSTOMERSCustomer_Id, Name, Street, City, State, Zip

ACCOUNTSCustomer_Id, Account_Number, Account_Type, Date_Opened, Balance Customer_Id is the key for the CUSTOMERS table. Account_Number is the key for the ACCOUNTS table. Customer_Id in the ACCOUNTS table is called a Foreign Key

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Customer

Column Data Type Size Customer_Id (Key) Integer 20 Name Character 30 Street Character 30 City Character 25 State Character 2 Zip Character 5

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Accounts

Column Data Type Size Customer_Id (FK) Integer 20 Account_Number (Key) Integer 15 Account_Type Character 2 Date_Opened Date Balance Real 12,2

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Example: Customer Table

Customer_Id Name Address City State Zip

1001 Mr. Smith 123 Lexington Smithville KY 91232

1002 Mrs. Jones 12 Davis Ave. Smithville KY 91232

1003 Mr. Axe 443 Grinder Ln. Broadville GA 81992

1004 Mr. & Mrs. Builder 661 Parker Rd. Streetville GA 81990

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Example: Accounts Table

Customer ID Account_Number Account_Type Date Opened Balance

1001 9987 Checking 10/12/89 4000.00

1001 9980 Savings 10/12/89 2000.00

1002 8811 Savings 01/05/92 1000.00

1003 4422 Checking 12/01/94 6000.00

1003 4433 Savings 12/01/94 9000.00

1004 3322 Savings 08/22/94 500.00

1004 1122 Checking 11/13/88 800.00

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Business Rules

Business rules allow us to specify constraints on what data can appear in tables and what operations can be performed on data in tables. For example:

An account balance can never be negative. A Customer can not be deleted if they have an

existing (open) account. Money can only be transferred from a "Savings"

account to a "Checking" account. Savings accounts with less than a $500 balance incur

a service charge.

How do we enforce business rules ? Constraints on the database

Applications

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Create, modify, drop Tables, views, and sequences

CREATE TABLE employee

(fname VARCHAR2(8), minit VARCHAR2(2), lname VARCHAR2(9), ssn VARCHAR2(9) NOT NULL, bdate DATE, address VARCHAR2(27), sex VARCHAR2(1), salary NUMBER(7) NOT NULL, superssn VARCHAR2(9), dno NUMBER(1) NOT NULL) ;CREATE TABLE dependant (

Last_Name d_last_name NOT NULL,

First_name VARCHAR(18) NOT NULL,

Soc_Sec d_soc_sec NOT NULL,

Date_of_Birth DATE,

Employee_Soc_Sec d_soc_sec NOT NULL );

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More DML- the Select command

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CREATE TABLE students (studentid NUMBER(5,0), name VARCHAR2(25), major VARCHAR2(15), gpa NUMBER(6,3), tutorid NUMBER(5,0));

INSERT INTO students VALUES (101, 'Bill', 'CIS', 3.45, 102); INSERT INTO students VALUES (102, 'Mary', 'CIS', 3.10, NULL); INSERT INTO students VALUES (103, 'Sue', 'Marketing', 2.95, 102); INSERT INTO students VALUES (104, 'Tom', 'Finance', 3.5, 106); INSERT INTO students VALUES (105, 'Alex', 'CIS', 2.75, 106); INSERT INTO students VALUES (106, 'Sam', 'Marketing', 3.25, 103); INSERT INTO students VALUES (107, 'Jane', 'Finance', 2.90, 102);

Example table COURSES:Create table courses(studentid NUMBER(5,0) NOT NULL, coursenumber VARCHAR2(15) NOT NULL, coursename VARCHAR2(25), semester VARCHAR2(10), year NUMBER(4,0), grade VARCHAR2(2)); INSERT INTO courses VALUES (101, 'CIS3400', 'DBMS I', 'FALL', 1997, 'B+'); INSERT INTO courses VALUES (101, 'CIS3100', 'OOP I', 'SPRING', 1999, 'A-'); INSERT INTO courses VALUES (101, 'MKT3000', 'Marketing', 'FALL', 1997, 'A'); INSERT INTO courses VALUES (102, 'CIS3400', 'DBMS I', 'SPRING', 1997, 'A-'); INSERT INTO courses VALUES (102, 'CIS3500', 'Network I', 'SUMMER', 1997, 'B'); INSERT INTO courses VALUES (102, 'CIS4500', 'Network II', 'FALL', 1997, 'B+'); INSERT INTO courses VALUES (103, 'MKT3100', 'Advertizing', 'SPRING', 1998, 'A'); INSERT INTO courses VALUES (103, 'MKT3000', 'Marketing', 'FALL', 1997, 'A'); INSERT INTO courses VALUES (103, 'MKT4100', 'Marketing II', 'SUMMER', 1998, 'A-');

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StudentID Name Major GPA TutorId

101 Bill CIS 3.45 102

102 Mary CIS 3.1

103 Sue Marketing 2.95 102

104 Tom Finance 3.5 106

105 Alex CIS 2.75 106

106 Sam Marketing 3.25 103

107 Jane Finance 2.9 102

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• Average GPA of all students•SELECT AVG(gpa) FROM students; AVG(GPA) ---------- 3.12857143

• Average GPA of Finance and CIS students:

• SELECT AVG(gpa) FROM students WHERE major = 'CIS' OR major = 'Finance'; AVG(GPA) ---------- 3.14

•Select all students whose major is CIS•Select * from students where major =‘CIS’

Some queries

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