Dbms Hindi

Database Management Systems

Developed By SMS (The best friends group) 1 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945

DATABASE MANAGEMENT SYSTEMS

UNIT – I Operational data, Purpose of database system, Views of data, Data models: Relational, Network, Hierarchical, Instances & Schemes, Data Dictionary, Types of Database languages: DDL, DML, Structures of a DBMS, Advantages & Disadvantages of a DBMS, 3- Level Architecture Proposal: External, Conceptual & Internal Levels, Entity Relationship Model as a tool of conceptual & Internal Levels, Entity Relationship Model as a tool of conceptual set, Attributes, Mapping Constraints, Keys, Entity-Relationship diagram (E-R diagram) : Strong & weak entities, Generalization, Specialization, Aggregation, Reducing ER diagram to tables UNIT – II Set theory concepts and fundamentals: Relations, Domains, Attributes, Tuple, Concepts of Keys: Candidate key, Primary Key, Alternate Key, Super Key, Foreign Key, Fundamental integrity rules: Entity integrity, Referential integrity, Extension & Intention, Relational Algebra : Select, Project, Cross product, Different types of joins i.e. theta join, equi join, natural join, outer join, set operations. Structure query language (SQL), Codd's rules. UNIT – III Functional Dependencies, Good & Bad Decomposition, Anomalies as a database: A consequences of bad design, Universal Relation, Normalization: First, Second, Third & BCNF Normal Forms, Multivalues Dependency, Join Dependency & forth Fifth Normal Form. UNIT – IV Basic Concepts – INDEXING & HASHING, Indexing: B+ tree Index Files, B-tree Index Files, Hashing : Static has functions, Dynamic Hash Functions, Index Definition in SQL : Multiple key Access. UNIT – V Failure Classification, The Storage Hierarchy, Transaction Model, Log Based Recovery, Buffer Management, Shadow Paging



Bachelor of Computer Application (BCA) Examination, December 2005 2BCA3 - DATA BASE MANAGEMENT SYSTEM

Unit I 1. gkfLiVy dk ,d E-R ekMy cukb;s ftlesa MkWDVj yksxksa dk ,d leqPp; gks vkSj jkfx;ksa dk ,d leqPp; gks] izR;sd jksxh

dk VsLV jksxksa ds lkFk Association n’kkZb,A Draw an E-R diagram for the database of hospital with a seat of patients and set of a Medical

Doctors with each patients a log of the various tests conducted is also associated. 20 2. ¼v½ Recursive lEcU/k dk D;k eryc gSa \ dqN mnkgj.k nsdj le>kb;sA What is meant by a Recursive relationship type? Give some examples of recursive relationship types. 10 ¼c½ nks Record based MkVk ekMy ds ykHk o gkfu dks ifjyf{kr dhft,A State the major advantage and disadvantage of the two record base data models. 10 Unit II 3. fuEu dh O;k[;k dhft,% ¼v½ lqij dh ¼c½ izkFkfed dh ¼l½ fjys’ku ,ytsczk esa Økl izksMsDV ¼n½ izktsDV vkijs’kuA Describe the following: (a) Super Key (b) Primary Ke (c) Cross Product in Relational Algebra (d) Project Operation. 20 4. ,l- D;w- ,y- ls vki D;k le>rs gks \ mnkgj.k lfgr SQL dh O;k[;k dhft,A What do you mean by S.Q.L.? Describe the SQL with example. 20 Unit III 5. fuEufyf[kr dh O;k[;k dhft,% Explain the following: (a) Tuple Entity (b) Normalization (c) Codd Rule (d) Universal Relation. 20 6. ¼v½ pkSFks (4 NF) vkSj ikapos (5 NF) esa dkSu&dkSu ls phtsa dkWeu gSa \ What are common factor in fourth and fifth normal form? 10 ¼c½ fuEu Relation }kjk larq"V dh tkus okyh lHkh Functional dependencies crkb,% List all functional dependencies satisfied by the following relation:

A B C a1

a1 a2 a2

b1 b1 b1 b1

c1 c2 c1 c2

Unit IV 7. B+ Vªh ij mnkgj.k lfgr ,d fucU/k fyf[k,A Write an essay on B+ tree with suitable example. 20 8. B- Vªh bUMsDl Qkby D;k gS \ mnkgj.k lfgr Mkbukfed gSl QaD’ku dh O;k[;k dhft,A What is B-tree index files? Describe Dynamic Hash Function with an example. 20 Unit V 9. ¼v½ Buffer Management D;k gS \ What is Buffer Management? ¼c½ fMLd [kjkc gksus ds mijkUr dksbZ Recovery Procedure crkb;sA Explain a recovery procedure that is needed after a disk crash. 10 10. ¼v½ MkVkcsl ds Transaction Model dh O;k[;k dhft,A Describe the Transaction Model of Database. 10 ¼c½ Failure Classification ds dqN egRoiw.kZ igywvksa dh O;k[;k dhft,A Describe some important features of failure classification. 10



Database Mangement system Interelated Data rFkk ml Data dks Access djus ds fy, fy[ks x;s Programs dk lewg gSa fdlh Hkh ,d Enterprise ls Related Data ds collection dks Database dgk tkrk gSaA DBMS dk izeq[k mn~ns'; Database Information dks lgh rFkk Convenient :i ls Store djuk gSaA Database System Application: - Database dbZ txg ij iz;ksx esa yh tkrh gSaA vr% mlds fuEu Application gSaA

(1) Banking ds fy, Use dh tkrh gSaA (2) Airline Reservation rFkk Information dk Schedule cukus ds fy,A (3) Universities esa Students ds Information rFkk course ds ckjs esa iwjh tkudkjh nsus ds fy,A (4) Monthly Satement dks cukus ds fy,A (5) Telecommunication ds fy,A (6) Finance esa Sales rFkk Purchase dh Information dks Store djukA (7) Sales esa Customer Product o Purchase Information dks j[kukA (8) Manufacturing esa Management ds Supply rFkk Warehouse o Order dh Information dks Store djukA (9) Human Resources ds vUrxZr Employee, salary, payroll, tax vkfn Information dks Store djukA

Database System Vs File System: - File System esa Data dks Store djds Operating System ij Store fd;k tkrk gSaA System Permanent Records dks dbZ Files esa j[krs gSa rFkk fdlh File ls Record izkIr djuk rFkk u;s record dks tksM+us ds fy, vyx&vyx izdkj ds Application Program dks Use djuk iM+rk gSaA DBMS ls igys Systems blh izdkj dh files esa Data dks Store djds j[krs Fks ijUrq DBMS }kjk file system ds Disadvantages dks nwj fd;k x;k o ;gh DBMS ds Advantage gksrs gSaA (1)Data Reduandancy ds dkj.k vf/kd Storage o vf/kd Access Cost yxrh gSaSaA Same Data dh Various Copies dh j[kus ls ,d le; esa lHkh dks ,d lkFk Update ugha fd;k tk ldrkA blh leL;k dks Data Inconsistency dgk tkrk gSaA (2) Difficulting in Accessing Data:- Data dks Access o Retrieve djus esa dfBukbZ u gks blds fy, fofHkUu Application Programs dks mi;ksx esa fy;k tkrk gSaA (3) Data Isolation:- Data o Processor dks ,d lkFk j[kus ls Application Programs ds }kjk vklkuh ls Data dks Access fd;k tk ldrk gSaA (4) Integrity Problem:- Data dks dqN Condition ds vk/kkj ij ,d lkFk DBMS esa j[kk tkrk gSaA (5) Atomicity Problem:- Computer System Mechanical o Electrical gksus ds dkj.k Faliure Occur gks ldrk gSaA ;fn Faliure Occur gks tk, rks MkVk dks MkVkcsl aaaRestore djuk vko’;d gksrk gSaA bls gh Atomicity dgk tkrk gSaA (6) Security:- gj User Database ds MkVk dks Access ugha dj ldrk gSaA flQZ MkVkcsl ds ,d ikVZ dks Access fd;k tk ldrk gSaA View of Data:- Database dk ,d y{; Users dks MkVk dk Abstract View Provide djuk gSa blesa system dh Details dks Hide fd;k tkrk gSaA ftlls MkVk dks fdl rjg Store o Maintain fd;k tk, Hkh ifjHkkf"kr fd;k tkrk gSaA Data Abstraction:- vr% MkVk dk laf{kIrhdj.k gh MkVk Abstraction dgykrk gsaA Database Users Computer Trained ugha gksrsA vr% Developers ds }kjk MkVkcal dh tfVyrk dks Users ls dj fn;k tkrk gSaA vr% laf{kIrhdj.k ds fuEu Level dks define fd;k x;k gSaA

(1) Physical Level:- ;g Abstraction dk lcls Lower Level gSa tks ;g ifjHkkf"kr djrk gSa fd MkVk dks okLro esa fdl izdkj LVksj fd;k tk,A Physical Level Data Structure Detail dh tfVyrk dks ifjHkkf"kr djrk gSaA

(2) Logical Level:- Abstraction dk vxyk level ;g ifjHkkf"kr djrk gSa fd Database esa D;k Data Store djuk gsa rFkk MkVk ds chp ds Relationship dks Maintain djukA

(3) View Level:- ;g Abstraction dk lcls mijh ysoy gSa tks flQZ Part of the Database dks ifjHkkf"kr djrk gSaA



Instances & Schema:- Information dk og Collection ftls fdlh {k.k MkVkcsl esa LVksj fd;k tkrk gSa mls Database Instance dgrs gSaA MkVkcsl dh iwjh Design dks MkVkcsl Schema dgk tkrk gSaA Schema dks Abstraction Levels ds vk/kkj ij ckaVk x;k gSa%&

(1) Physical Schema:- ;g Physical Level dh MkVkcsl design dks ifjHkkf"kr djrk gSaA (2) Logical Level Schema:- blesa Logical Level dh fMtkbu dks ifjHkkf"kr fd;k tkrk gSaA

View Level ij Hkh MkVkcsl ds cgqr ls Define fd;k tkrk gSa ftls Subschema dgrs gSaA ftlesa Database ds Different Views dks define fd;k x;k gSaA Data Models:- Database Structure gh Data Model gSaA Data esa laca/k] Consistency Constraint o MkVk ds dkYifud Tools dks ifjHkkf"kr djuk gh Data Models ds eq[; dk;Z gSaA fuEu Data Models dks define fd;k x;k gSa%&

(1) E-R Models (2) Relational Model (3) Object Oriented Data Model (4) Object Relational Data Model (5) Network Data Model (6) Hierarchical Data Model

(1) E-R Model:- os Real World Objects ftUgsa vU; Objects ls differentiate fd;k tk ldrk gSa] mUgsa Entity dgrs gSaA Entities dks Attributes ds Li esa Database esa ifjHkkf"kr fd;k tkrk gSaA tSls A/c Number, A/c Balance vkfn Attributes gSa ftls Account Entity esa define fd;k x;k gSaA fofHkUu Entities ds e/; laca/k LFkkfir djuk gh Relationship dgykrh gSaA Database ds Logical Structure dks E-R diagram ds }kjk ifjHkkf"kr fd;k x;k gSa%& (1) Rectangles ( )- Entity Set dks iznf’kZr fd;k tkrk gSaA (2) Ellipse ( ) – blesa Attributes dks iznf’kZr fd;k tkrk gSaA (3) Diamonds ( ):- blds }kjk Entity Set ds e/; Relationship dks lsV fd;k tkrk gSaA (4) Lines (-):- Entity Set o Entity dks tksM+us ds fy;s Lines dks mi;ksx esa fy;k tkrk gSaA E-R Model esa fuEu Attributes dks ifjHkkf"kr fd;k x;k gSa%&

(1) Simple Value Attribute (2) Compsite Value Attribute (3) Single Value Attribute (4) Derived Attribute

View1 View2 ViewN View level

Logic level

Cust-ID

Customer name Customer Street

Customer City

Customer Depositor

Account

Account Number Balance



(1) Simple Attributes:- Simple Attributes dks Parts ¼vU; Hkkxksa½ esa fofHkUu ugha fd;k tk ldrkA Example:- Loan Number, Amount vkfnA (2) Composite Value Attributes:- Composite Attributes os Attributes gSa ftUgsa Sbparts esa Devide ¼foHkDr½ fd;k tk ldrk gSaA tSls%& Name ,d Composite Attribute gSa tSls%& First name, Middle Name o Cost Name vkfnA (3) Single Value Attribute:- ;s Attributes ftudh Value ges’kk ,d gh jgrh gSa tSls%& ,d Customer ;fn cgqr ls yksu ysrk gSa rks Loan No. ges’kk vyx&vyx gksxsaA vr% ;g ,d Single Value Attribute gSaA (4) Multi valued Attribute:- tc fdlh Attribute dh ,d ls T;knk Values gks rks mls Multivalue Attribute dgk tkrk gSaA tSls%& Phone Number Multi value Attribute gSa D;ksafd ,d Customer ds ,d ls T;nk (0,1,2,………n) Phone Numbers gks ldrs gSaA (5) Derived Attribute:- bl izdkj ds Attributes dks fofHkUu vU; Attributes ls Derive fd;k x;k gSaA tSls ;fn ,d Customer us cgqr ls yksu ys j[ks gSa rks og irk yxk;k tk ldrk gSa fd Customer us Bank ls fdruk yksu fy;k gSaA Relationship & Relationship Set:- fofHkUu Entities ds e/; laca/k LFkkfir djuk gks Relationship dgykrh gSaA tSls Customer Table dk yksu Vscy ls lacaf/kr gksukA Same Type ds Relations dks ,d lkFk ,df=r dj j[kuk gh Relationship Set dgykrk gSa tSls nks Entity Set Customer o yksu ds e/; Borrower Relationship gSa tks Customer o yksu ds e/; Relationship dks iznf’kZr djrk gSaA fdlh Hkh Entity Set dh Primary Key ds }kjk fofHkUu Entity Set dks vU; Entity Set ls i`Fkd fd;k tk ldrk gSaA (2) Relational Model ¼fjys’kuy ekWMy½:- Relational Model Tables dk Collection gSa ftlesa Data rFkk Relationship dks iznf’kZr fd;k tkrk gSaA gj Vscy esa Multiple Columns rFkk gj Column dk ,d vyx uke gksrk gSaA Relational Model dks Record Based Model dk ,d mnkgj.k Hkh ekuk tkrk gSa D;ksafd blesa Records dks Fixed Format esa LVksj fd;k tkrk gSaA Relational Model dk abstraction level E-R Model dh vis{kk Lower gksrk gSaA Database dks igys E-R Model ds :i esa Design fd;k tkrk gSaA ckn esa mls Relational Model esa Translate dj fn;k tkrk gSaA (3) Object Oriented Data Model:- bls E-R Model dk Extension Hkh dgk tkrk gSa ftleas Encapsulation ¼lHkh MkVk tks Related gks dks ,d lkFk j[kuk½ Methods ¼ftlls Database ls MkVk dks Access fd;k tk lds½ o Object Identity (Object dh igpku) dks ifjHkkf"kr fd;k tkrk gSaA E-R Model dh ,d Entity dks Object dgk tkrk gSaA tc MkVk rFkk mls Access djus ds Methods dks ,d lkFk Single Unit esa j[kk tkrk gSa rks bls Object Oriented Model dh ,d Property Encapsulation dgk tkrk gSaA ftlds Contents dks ckgjh rRoksa }kjk ugha ns[kk tk ldrkA (4) Object Relational Data Model:- Object Relational Data Model esa Object Oriented Data Model o Relational Data Model nksuksa dks 'kkfey fd;k tkrk gSaA Data Dictionary:- Data Dictionary esa Meta data (Data About Data) dks j[kk tkrk gSaA Table dh Design Metadata dk gh ,d mnkgj.k gSaA Data Dictionary esa fuEu Information dks LVksj fd;k tkrk gSaA

(1) Name of the Relation (Relation dk uke) (2) Names of the Attributes of Each Relation (Relation ds gj Attributes dk uke) (3) Length of Attributes (Attribute dh yEckbZ) (4) Integrity Constraints ¼MsVk dks ,d lkFk j[kus ds fy;s miyC/k 'krsZ½ cgqr ls lhLVe esa User ls laca/khr MkVk dks

Hkh LVksj fd;k tkrk gSa tSls%& (1) Name of The Authorized User (2) User ls laca/khr Accounts dks lwpuk



(3) Password ;k vU; lwpuk,aA Database Languages:- Database ds }kjk fuEu nks Hkk"kkvksa dks iz;ksx esa fy;k tkrk gSa%& (1) DDL:- Database Design o mlls laca/khr fofHkUu ifjHkk"kkvksa ds laxzg dks ,d Special Hkk"kk ds }kjk iznf’kZr fd;k tkrk gSa ftls DDl dgrs gSaA mnkjg.k ds fy;s%& Create Table Account (a/c_number valchar(20), balance number (4) mijksDr Statement ds }kjk a/c Table dks Create fd;k x;k gSaA blds (DDl) }kjk Data dicitionary dks Hkh Update fd;k tk ldrk gSaA tc fdlh Hkh MkVk dks Read ;k Modify djuk gks rks Database System lcls igys Data Dictionary dks pSd djrk gSaA MkVkcsl dk Storage Structure o Access Method dks ,d Special DDL esa j[kk tkrk gSa ftls Data Storage and definition Language (DSDL) dgk tkrk gSa ;s Information User ls Nqih jgrh gSaA Data Manipulation Language (DML):- Data Manipulation dk vFkZ gSa%&

(1) Database esa Store Information dks Access djukA (2) u;h Information dks MkVkcsl dks LVksj djukA (3) MkVkcsl dks mifLFkr Information dks Delete djukA (4) Database esa mifLFkr Information dks Modify djukA

DML dks eq[;r% nks Hkkxksa esa ck¡Vk x;k gSa%& (1) Procedural DML (2) Declaration DML

(1) Procedural DML dh vko’;drk user dks blfy;s gksrh gSa D;ksafd ;g user dks fdlh Data dh vko’;drk gSa o ml

MkVk dks dSls Access fd;k tk ldrk gSaA ds ckjs esa crkrh gSaA (2) Declaration DML:- mls Non Procedural DML Hkh dgk tkrk gSa D;ksafd blesa flQZ MkVk dh vko’;drk dks

iznf’kZr fd;k tkrk gSa ijUrq ;g define ugha fd;k tkrk fd MkVk dks fdl izdkj Access fd;k tk,A Database dks Information dks Access djus ds fy;s Query dks mi;ksx esa fy;k tkrk gSaA DML dk og Hkkx tks lwpuk dks Relational ds fy;s mi;ksx esa fy;k tkrk gSa mls Query Language dgk tkrk gSaA

Database System Structure:- Database System dh Modules esa foHkkftr fd;k x;k gSa rFkk gj Module ij System Control ls laca/khr ftEesnkjh gksrh gSaA Database System dks Functionally nks Hkkxksa esa foHkkftr fd;k x;k gSa%&

(1) Storage Manager (2) Query Processor Components

(1) Storage Manager:- Storage Manager Program dk og Module gSa tks Low Level Data rFkk Application Programs o Queries ds e/; Interaction djrk gSaA Storage Manager File System Commands esa ifjofrZr djus dk dk;Z Hkh djrk gsaA vr% Storage Manager Data ds Relational o Updation ds fy;s mÙkjnk;h gksrk gSaA

Storage Manager esa fuEu rRoksa dks 'kkfey fd;k tkrk gSa%& (1) Authorization and Integrity Manager:- blesa MkVk ds Integrity Constraints rFkk Users dh Authority

dh Hkh pSd fd;k tkrk gSaA (2) Transaction Manger:- ;g Database dh Ensistancy ds fy;s mÙkjnk;h gksrk gSa rFkk Transaction dks yxkrkj

fcuk O;o/kku Execute djus dk dk;Z Hkh djrk gSaA (3) File Manager:- blds }kjk Disk Space o MkVk Structure dks iznf’kZr fd;k tkrk gSaA (4) Buffer Manager:- Data dks Main Memory esa ykus ds fy;s mÙkjnk;h gksrk gSaA

Storage Manager ds }kjk fofHkUu Data Structure dks Implement fd;k tkrk gSa%& (1) Data files:- ftlesa Data Store jgrk gSaA (2) Data Dictionary:- ftlesa Data About Data dks j[kk tkrk gSaA (3) Indices:- blesa MkVk dks Fast Access fd;k tk ldrk gSaA



(2) Query Processor:- Query Processor Components dks Include fd;k x;k gSa%& (1) DDL Interpreter:- tks DDL Statement dks Interpreter djrk gSa rFkk mu Statement dh ijhHkk"kk dks Data

Dictionary esa Store djrk gSaA (2) DMl Compiler:- ;g DML Statements dks Low-level Instruction esa ifjofrZr djus dk dk;Z djrk gSaA (3) Query Evaluation Engine:- ;g DML Compiler }kjk Generated Low-Level Instruction dks Execute

djus dk dk;Z djrk gSaA Application Architecture:- Database Applications dks nks Hkkxksa esa foHkDr fd;k x;k gSa%&

(1) Two Tier Architecture (2) Three Tier Architecture

(1) Two Tier Architecture:- blesa Application dks Component esa ck¡Vk tkrk gSa ftls Client Machine ij j[kk tkrk gSaA bl Component }kjk Database System dh Functionality dks Server Machine ij Query Language dh lgk;rk ls Access fd;k tkrk gSaA Client o Server ds e/; Interactoin dk dk;Z ODBC (Open Database Connectivity) ;k JDBC (JAVA Database Connectivity) }kjk fd;k tkrk gSaA

Native /naiveUs

ers

Application Programmer

Sophisticated Users

Database Aministrator

Application Interface

Application Programs

Query Tools

Administrator Tools

Use Write Use Use

Compiler & Linker

DML Queries

DDL Interpreter

Application Program

Object Code

DML Compiler & Organizer

Query Evaluation Engine

Query Processor

Buffer Manager

File Manager

Authorization Integrity Manager

Transaction Manager

Storage Manager

Data Dictionary

Statistical Data

Indices Data

Disk Storage

Index



(2) 3- Tier Architecture:- blesa Client Machine dh Front end ds :i esa iz;ksx esa fy;k tkrk gS rFkk ;g e’khu Directly Database Calls dks ugha j[krhA Client e’khu forms ds }kjk Application Server ls Internet djrh gSaA Application Server ckn esa Database dks Database dks Access djrk gSaA cM+h Application ds fy;s Three-tier dh mi;qDr jgrk gSaA ftls www (World Wide Web) ij ju fd;k tk ldrk gSaA

ADVANTAGES & DISADVANTAGES OF DBMS ADVANTAGES %&

(1) Redundancy Control:- DBMS ds }kjk gj Logical Data Item dks ,d txg LVksj fd;k tkrk gSa ftlls Information dh vusd Copies ugha curh o T;knk Storage Space Hkh ugha yxrk gSaA ftlls T;knk Updation dh Problem Hkh ugha vkrhA

(2) Access Control:- Database Administrator lqj{kk (Security) o Authorization dks mi;ksx ds fy;s miyC/k djokrk gSaa vr% DBA ;k Data rFkk User nksuks ij iwjk Control gksrk gSaA

(3) Program Object rFkk Data Structure ds fy;s iw.kZ LVksjst%& Objects ftUgsa Database esas Store fd;k tkrk gSa ;s Program Execution rFkk Transmination ds fy;s mÙkjnk;h gksrk gSA Database esa mifLFkr MkVk dks ckj&ckj dbZ User }kjk mi;ksx esa fy;k tk ldrk gSaA

(4) Multiple User Interface:- gj User Database ls vius Lo;a ds izksxzke o Interface ds vk/kkj ij Interact djrk gSa bu Interface dks fofHkUu izksxzkfeax Hkk"kkvksa esa develop fd;k tk ldrk gSaA ijUrq mudk Database ls Compalible gksuk vko’;d gSaA

(5) Data dks Enter djus ds fy;s DBMS }kjk cgqr lh lhekvksa dks ifjHkkf"kr fd;k tkrk gSa rFkk bUgsa Process }kjk mi;ksx Hkh fd;k tkrk gSaA

(6) Backup & Recovery:- DBMS Faliure ds dkj.k dbZ ckj Problem esa vk tkrk gSa] ijUrq DBMS }kjk Faliure (Hardware ;k Software) ls Recover gksus ds Hkh dbZ lk/ku miyC/k gSa ftlesa MkVk dks Inconsistent Data esa vkus ls cpk;k tk ldrk gSaA

(7) Data Sharing:- ge tkurs gSa fd DBMS esa MkVk dh flQZ ,d gh dkWih LVksj gksrh gSa blh dkWih dks cgqr ls Users }kjk mi;ksx esa fy;k tkrk gSaA

(8) Data Abstraction dk xq.k gksus ds dkj.k MkVkcsl ds Structure dks fcuk Users dks ijs’kku ;k Disturb fd;s Modification fd;k tk ldrk gSaA

(9) Database gj le; Users dks Latest Information Provide djrk gSaA

USER

Application

Client USER

Application

Database System

APPLICATION SERVER

Database System

Network Network

Server

2-Tier Architecture

3-Tier Architecture



DISADVANTAGES :- (1) Database System ds fy;s izkjfEHkd Investment vf/kd gksrk gSa ftlesa Hardware Software o vU;

Trainings Hkh 'kkehy gksrh gSaA vxj Cost High gks rks nwljk rjhdk <w¡< ysuk pkfg;sA (2) DBMS ds lkFk vU; mifjO;;ksa tSls Security Concurrency Control, Recovery rFkk Integrity

Constriants vkfn dks Hkh 'kkfey djuk vko’;d gksrk gSaA (3) dqN ifjfLFkfr;k¡ ftlesa Database rFkk mu ij mi;ksx yh tkus okyh Application Simple gks rFkk ,d yEcs le;

rd ;fn mls Change u djuk gks rks DBMS dk iw.kZ mi;ksx ugha fd;k tk,xkA rFkk mlds dqN Features dks mi;ksx esa ugha fy;k tkrkA

(4) dHkh&2 Database System dks Sigle User ds fy;s gh cuk;k tkrk gSaA blds fy;s Hkh DBMS Suitable ugha gSaA MPPING CONSTRAINTS:- Enitity rFkk Relationship dks fuEu lhekvksa ds vUrxZr ifjHkkf"kr fd;k tkrk gSa%&

(1) MAPPING CARDINALITIES ¼esfiax dkMZusfyfV½ (2) Participation Constraints ¼ikfVZflis’ku dUlVªsaV½

(1) MAPPING CARDINALITY:- bUgsa 4 Hkkxksa esa ck¡Vk x;k gSa%& (1) One to One:- Entity A vf/kd ls vf/kd B dh ,d Entity ls Connected gks rFkk B dh ,d Entity vf/kd ls

vf/kd A dh ,d Entity ls laca/khr gksA

ONE to ONE (2) One to Many:- A dh ,d Entity b dh cgqr lh Entity ls laca/khr gks ldrh gSaA ijUrq b dh ,d Entity vf/kd

ls vf/kd A dh ,d Entity ls gh laca/khr gks ldrh gSaA

One to Many

(3) Many to One:- A dh ,d Entity vf/kd ls vf/kd B dh ,d Entity ls laca/khr gks ldrh gSaA ijUrq B dh ,d Entity A dh cgqr lh Entities ls laca/khr gks ldrh gSaA

Many to One (4) Many to Many:- A dh vusd Entities B dh vusd Entities ls laca/khr gks ldrh gSa] mlh izdkj B dh vusd

Entities A dh vusd Entities ls laca/khr gks ldrh gSaA

Many to Many

a1 a2 a3

b1 b2 b3

a1 a2 a3

b1 b2 b3 b4 b5

a1 a2 a3 a4 a5

b1 b2 b4

a1 a2 a3 a4

b1 b2 b3 b4



KEYS:- (1) Super Key:- Super Key ,d ;k ,d ls vf/kd Attributes dk lewg gSa ftlls fdlh Entity Set dks Uniquely fd;k tk ldrk gSA tSls Customer Table ftlesa (Customer ID, Customer Name, Customer City) vkfn gSa ds fy;s Customer_id Super Key gSa D;ksafd blls Customer Table dks Uniquly Identify fd;k tk ldrk gSaA mlh izdkj (Customer_id + Customer_name, Customer_id _ Customer_city) Hkh Super Key gSa D;ksafd buls Hkh Customer Table dks Uniquely Identify fd;k tk ldrk gSaA ijUrq Customer name, Customer City dks Super Key ugha ekuk tk ldrk D;ksafd Customer dk uke ;k Customer dh City Same gks ldrh gSaA

(2) Candidate Key:- Super dh dk Concept User ds fy;s i;kZIr ugha gksrk gSaA D;ksafd Super Key esa dqN Extra Attributes dks Hkh 'kkfey fd;k tkrk gSaA vr% Super Key dk Minimisation djuk Candidate Key dgykrh gSaA Customer_name o Customer Street nksuksa Attributes ds }kjk Customer Table ds Record dks Uniquely identify fd;k tk ldrk gSaA vr% Customer_id o Customer name + Customer_Street nksuks Candidate Key gksxhA ijUrq Customer name, Customer City o Customer_id dk Combination Candidate Key ugha gksrk gSaA

(3) Primary Key:- Candidate Key esa ls fdlh ,d Key dks as a Primary Key Choose dj fy;k tkrk gSaA ¼ijUrq ;g ckr /;ku j[kuh vko’;d gksrh gSa fd Primary Key esa dHkh Hkh Null Value½ dks Conidor ugha fd;k tkrk gSaA vr% Primary Key esa Null Value gks ldrh gSaA

(4) Composite Key:- dHkh&2 Relation ;k Table esa dksbZ Hkh ,d Key ugha gksrh ftls Primary Key cuk;k tk ldsA vr% nks Attributes dks bdV~Bk dj mls Primary Key cuk;k tkrk gSa mls Comosite Key dgrs gSaA

(5) Foreign Key:- tc fdlh ,d Table dh Primary Key dks nwljh Table esa Hkh iznf’kZr djuk gks rks nwljh Table esa og Primary Key Attribute Foreign Key dgykrk gSaA

E-R Diagram:- E-R Diagram ds }kjk MkVkcsl ds Logical Structure dks Graphically iznf’kZr fd;k tkrk gSaA E-R Model ds dqN rRo fuEu gSa%& (1) Rectangles:- ( ) Entity Set dks blds }kjk iznf’kZr fd;k tkrk gSaA (2) Ellipses:- ( ) blds }kjk Attributes dks iznf’kZr fd;k tkrk gSaA (3) Diamonds:- ( ):- blds }kjk Relationship Set dks iznf’kZr fd;k tkrk gSaA (4) Lines:- (&&):- Entity o Entity Set ds chp esa Relationship dks Link ds }kjk iznf’kZr fd;k tkrk gSaA (5) Double Ellipses ( ):- Multi value Attributes dks iznf’kZr fd;k tkrk gSaA (6) Dashed Ellipses ( ):- blds }kjk derived Attributes dks iznf’kZr fd;k tkrk gSaA (7) Double Rectangles:- ( ):- Weak Entity Set dks Double Rectangle ds }kjk iznf’kZr fd;k tkrk gSaA E-R Diagram ds }kjk Mapping Eardinality dks Hkh iznf’kZr fd;k tk ldrk gSaA (1) One to One:- iznf’kZr djus ds fy, ( ) dks mi;ksx esa ysrs gSaA (2) One to Many:- iznf’kZr djus ds fy, ( ) dks mi;ksx esa ysrs gSaA (3) Many to One:- iznf’kZr djus ds fy, ( ) dks mi;ksx esa ysrs gSaA (4) Many to Many:- iznf’kZr djus ds fy, ( ) dks mi;ksx esa ysrs gSaA

One to One

Cust-ID

Customer_name Customer_Street

Customer_City

Customer Borrower

Loan

Loan Number Amount



One to Many

Many to One

Many to Many

STRONG & WEAK ENTITY SET:- dqN ,sls Entity Set gksrs gSa ftuesa Primary Key dks Define gh ugha fd;k tk ldrkA bl izdkj ds Entity Set dks Weak Entity Set dgrs gSaA ijUrq tc fdlh Entity Set esa Primary Key dks define fd;k tkrk gSa rks mls Strong Entity Set dgrs gSaA Weak Entity Set dks Meaning ful cukus ds fy;s mls fdlh nwljh Entity ls dusDV fd;k tkrk gSaA ml Entity Set dks Identity ;k Owner Entity Set dgk tkrk gSa rFkk og Weak Entity Set Owner Entity Set ij dependent gksrk gSaA Generalization:- Database design Process dks Bottom up /kkj.kk esa Hkh cuk;k tk ldrk gSa ftlesa Multiple Entity Sets dks higher Level Entity Set esa muds Common Features ds vk/kkj ij ifjofrZr dj fn;k tkrk gSaA Agreegation:- blesa fdlh Database Retrieval Process esas No. of Inputs ds vk/kkj ij Single Output Generate fd;k tkrk gSa tSls ;fn dEiuh esa dke djus okys Employees dh Gross Salary fudkyuh gSa rks No. of Inputs eas lHkh Employees dh Dalary vk,xh rFkk mldk Output ,d vFkkZr~ Gross Salary gksxkA Reducing E-R diagrams into Tables:- (E-R Diagram dks Vscy esa ifjofrZ djuk) E-R Database Schema dks Group of Table esa j[kk tk ldrk gSaA Database ds gj Entity Set o Relationship Set dks ,d vyx Vscy esa Store fd;k tkrk gSa] o mls ,d vyx uke ls ifjHkkf"kr djrs gSaA

Cust-ID

Customer_name

Customer_Street

Customer_City

Customer Borrower

Loan

Loan Number Amount

Cust-ID

Customer_name

Customer_Street

Customer_City

Customer Borrower

Loan

Loan Number Amount

Cust-ID

Customer_name

Customer_Street

Customer_City

Customer Borrower

Loan

Loan Number Amount



E-R Model rFkk Relation Model nksuks gh Relation World Entities dks iznf’kZr djrs gSaA vr% nks Model tks ,d ls design Principles dks Follow djrs gSa vr% E-R Design dks Relational Design esa ifjofrZr dj fn;k tkrk gSaA

CUSTOMER

NAME CUST_ID ADDRESS CITY RAM 404 M.G. ROAD JODHPUR

(1) E-R Diagram ls ifjofrZr Vscy dks Relation dgrs gSaA (2) Table ds Colums dks Attributes dgk tkrk gSaA (3) ,d Record dks Tuple dgrs gSaA (4) fdlh Attributes esa mifLFkr Value dks Domain dgrs gSaA

Relation

Attributes

Tuple

Domain



UNIT-II Integrity Rules:- Integrity Constrains ds }kjk ;g Ensure fd;k tkrk gSa fd Authorized Users ds }kjk tc MkVkcsl esa dqN cnyko fd;s tkrs gSa rks mlls MkVkcsl esa Inconsistency Maintain ugha gksrhA “Integrity Constraints ls eq[; rkRi;Z ;g gSa fd Data dks dqN lhekvksa ds vUrxZr ,d lkFk j[kuk ftlls MkVkcsl esa Consistency cuh jgsaA Integrity Constraints dks eq[;r% 4 Hkkxksa eas ckaVk x;k gSa%&

(1) Domain Integrity (2) Entity Integrity (3) Referential Integrity (4) User defined Integrity

(1) Domain Integrity:- Data Base ds fdlh Relation esa fdlh Attribute esa Insert dh xbZ Value dks Domain dgk tkrk gSaA vr% fdlh Hkh Attribute esa Data dh Possible Value dks Insert djuk gh Domain Integrity dgykrk gSaA ;fn fdlh Record ds Particular Domain esa Value ugha Mkyh xbZ gSa rks mlesa Value dks Insert dj fn;k tkrk gSaA (2) Entity Integrity:- lHkh Real World Objects dks Entity dgk tkrk gSa o gj Entity ,d nwljs ls vyx gksrh gSaA tc fdlh ,d Entity Set dh Entity esa ,d gh Data Type dh Values fd;k tkrk gSa rks mls Entity Integrity dgk tkrk gSaA (3) Referential Integrity:- Referential Integrity Foreign Key ij fuHkZj djrh gSaA tc fdlh Vscy dh Primary Key Attribute dks fdlh nwljh Vscy esa Hkh Consider fd;k tkrk gSa rks nwljh Vscy esa ogh Attribute Foreign Key Attribute dgykrk gSaA vr% nksuks Relation ds Key Attributes dh Value Hkh leku gksuh pkfg,A bl izdkj ds Constraint ¼lhek½ dks Referential Integrity dgk tkrk gSaA (4) User Defined Integrity:- mijksDr Integrity Constraints ds vykok User dqN vU; Integrity Constraints dks Hkh Database ij Implement dgk tkrk gSaA tSls Database esa fdlh Hkh Record dks Insert djus ds fy;s 1st Letter dks Capital fy[kuk vkfnA

RELATIONAL ALGEBRA (1) Relation Algebra Procedural Query Language gSaA (2) blesa Input ds :i esa ,d ;k nks Relation dks fy;k tkrk gSa o Result ds :i esa ,d u;k Relation curk gSaA (3) Relational Algebra ds eq[; Operations Select, Project, Union, Set Difference o Cartesian Product

gSaA FUNDAMENTAL OPERATION OF RELATIONAL ALGEBRA :-

(1) Select Project Operations dks Unary Operation dgk tkrk gSa D;ksafd os flQZ ,d Relation ij Operation Perform djrs gSaA

(2) vU; rhu Operations Union, Set difference o Cartesian Product dks Binary Operations dgk tkrk gSa D;ksafd bUgsa Perform djus ds fy, nks Relations dh vko’;drk gSaA

(1) Select Operation:- Select Operation ds }kjk nh xbZ Condition ds vk/kkj ij Topless dks Select fd;k tkrk gSaA Selection ds fy;s xzhd Letter Sigma dks mi;ksx esa fy;k tkrk gSa Slect Operation ds lkFk =, #, <, <, >, > vkfnA Operation dh Hkh mi;ksx esa fy;k tk ldrk gSaA Selection Operation ds lkFk Logical Operation Perform djus ds fy;s Logical Operator dks mi;ksx esa fy;k tkrk gSaA blds fy;s and(^), or (v), Not (¬ ) Symbol dks mi;ksx esa ysrs gSaA Example:- (1) Loan Relation esa ls Delhi Branch ds Records dks lysDV djukA

branch-name = ‘Delhi’ (LOAN) (2) Loan Relation esa ls mu Records dks Select djuk ftudk Amount >1200 gksA

Amount >1200 (LOAN)



(3) Loan Relation esa ls mu Records dks Select djuk ftudk Amount >1200 o Branch delhi gksA branch-name = ‘Delhi’ ^ Amount >1200 (LOAN)

(2) Project Operation :- ;fn Selected Data dh List dks Display djuk gks rks Project dks mi;ksx esa fy;k tkrk gSa blds fy;s xzhd Letter (∏ ) dks mi;ksx esa ysrs gSaA Example:- (1) 10 and Relation esa ls Loan no o Amount Attributes dks Display djukA

∏ Loan No., amount (Loan) COMBINATION OF SELECT & PROJECT:- (1) fdlh Hkh Relation dh Information dks Condition ds lkFk Display djus ds fy;s Select o Project nksuks Operations dks mi;ksx esa fy;k tkrk gSaA tSls%& mu Customers dh Information dks Display djuk tks Delhi Brach esa jgrs gSaA

∏ Customer_name (Branch_name = ‘Delhi’(Customer)) CARTESIAN PRODUCT OPERATION:- Cartesian Product Operation dh x }kjk denote fd;k tkrk gSa ;g Binary Operation gSa ftlesa nks Relation ij Operations Perform fd;s tkrs gSa bl Operation dks Perform fuEu nks Condition esa fd;k tk ldrk gSaA

(1) nksuks Relation ftl ij Cartesian Product Perform djuk gSa esa dksbZ ,d Column Same gksu vko’;d gSaA (2) nksuks Table esa ,d Column leku gksrk gSa rks mls Relation Name o Dot (.) Operator }kjk vyx vyx fd;k

tk ldrk gSaA Cartesian Product dk Result Records ds Product ds :i esa vkrk gSaA tSls ;fn ,d Relation esa 4 Records o nwljs esa 5 Records gSa rks Result ds :i esa (5x4) = 20 Records dh Display fd;k tk,xkA Cartesian Product dks fuEu izdkj Perform fd;k tk,xkA

Relation 1 Relation 2 1 5 2 6 3 7 4 8

Relation1 × Relation2 (1,5), (1,6), (1,7), (1,8), (2,5), (2,6), (2,7), (2,8), (3,5), (3,6), (3,7), (3,8), (4,5), (4,6), (4,7), (4,8) Example:- ;fn mu lHkh Customers ds uke dks Find Out djuk gSa ftUgksus Delhi Branch ls loan fy;k gSa rks blds fy;s fuEu Relation Algebra Query dks fy;k tk,xkA

∏ namecust _ ( branch_name = ‘Delhi’ (borrower X loan))

SET OPERATIONS:- (1) Union Operations:- Relational Algebra esa Union Operation dh (U) ds }kjk denote fd;k tkrk gSaA Union Operation esa nks Relation dks ,d Relation dh rjg Display fd;k tkrk gSa lkFk gh Relation esa mifLFkr Duplicates dks Hkh Remove dj fn;k tkrk gSaA tc nks Relation ij Union (U) Operation dks Perform fd;k tkrk gSa] rks Union ,d Relation Display djrk gSa ftlesa R1 Relation ds o R2 Relation ds lHkh Tuples gksrs gSa ijUrq duplicates dks Remove dj fn;k tkrk gSaA Example:- ;fn Bank ds mu lHkh Customer dh List dks Display djuk gSa ftudk Bank esa Account gks ;k ftlesa Bank ls Loan ys j[kk gks ;k nksuksa rks blds fy;s fuEu Query dks Perform fd;k tk,xk%&

∏ amecustomer_n (borrower) U ∏ amecustomer_n (depositor)

Union Operation Perform djus ds fy;s fuEu nks ckrksa dks /;ku esa j[kuk vko’;d gSa%& (1) nksuks Relations esa Same Number of Attributes dk gksuk vko’;d gSaA (2) nksuksa Relation esa fdlh ,d Attribute dk leku gksuk vko’;d gSaA



(2) Intersection:- Relational Algebra esa Intersection Operation dks ( ∩ ) ds }kjk denote fd;k tkrk gSaA blesa Hkh duplicates dks Remove dj fn;k tkrk gSaA tc nks Relation ij Intersection (∩ ) Operation Perform fd;k tkrk gSa] rks Intersection ,d Relation Display djrk gSa ftlesa Relation R1 ds os Records tks Relation R2 esa Hkh mifLFkr gks (Common) dks Display fd;k tkrk gSaA Example:- ;fn Bank ds mu Customer dks Find Out djuk gks ftudk cSad esa ,dkmUV Hkh gks o ftUgksaus cSad ls yksu Hkh ys j[kk gksA

∏ amecustomer_n (borrower) ∩ Customer_name (depositor)

(3) SET- Difference:- Relation Algebra esa Set Difference Operation dks (-) ds }kjk denote fd;k tkrk gSa blesa Hkh duplicates dks Remove fd;k tkrk gSaA tc nks Relation ij Set difference Operation dks Apply djrs gSa rks blesa Result ds :i ea mu Records dks Display fd;k tkrk gSa tks R1 Relation esa rks gSa ijUrq R2 Relation esa ughaA Example:- cSad ds lHkh Customer Name dh List dks Display djuk ftldk Bank esa Account gks ij mlus cSad ls yksu ugha fy;k gSa rks blds fy;s fuEu Query dh tk,xhA

∏ amecustomer_n (depositor) - ∏ amecustomer_n (borrower)

SQL:- (Structured Query Language):- SQL dks San Jose Laboratory esa IBM }kjk developed fd;k x;k FkkA SQL dks cgqr ls Parts ls feydj cuk;k x;k gSa%&

(1) DDL (Data Definition Language):- SQL DDL ds }kjk Relation Rchema dks define, delete o Modify djus ds Commands dks Provide djok;k tkrk gSaA

(2) Interactive DML (Data Manipulation Language):- blesa Tuples dks Insert, delete o Modify djus ds Commands dks Insert fd;k tkrk gSaA

(3) View Definition:- View define djus ds fy;s SQL DDL esa Commands dks Store fd;k tkrk gSaA (4) Transaction Control:- Transaction dh Beginning o Ending esa Hkh SQL Commands dks Include fd;k

tkrk gSaA (5) Authorization:- Relation o View dks Access djus ds fy;s Login Password fn;s tkrs gSaA

Relation Database Relations dk Collection gSa ftlesa gj Relation dks Unique name fn;k tkrk gSa Data base esa Unknown Values ds Insertion dks jksdus ds fy;s Null Values dks Insert fd;k tkrk gSaA SQL dk Basic Structure rhu Clauses ij fuHkZj djrk gSa%& (1) Select (2) From (3) Where

• Select Operation Relational Algebra ds (π ) Projection Operation dh rjg gSaA • From Clause Relational Algebra ds Cartesian Product ds leku gSaA (x) • Where Clause Relational Algebra ds Selected ( ) Operation dh rjg gSaA

(1) Select Clause:- Select Clause ds }kjk Records dks Display fd;k tkrk gSaA Example:- ;fn Loan Relation ls lHkh Branch_name dks Display djokuk gSa rks fuEu Query dh tk,xh%& Select branch_name From loan ;fn Relation esa ls duplicates dks Rename djuk gks rks distinct Keyword dks Select fd;k tkrk gSaA Select distinct branch_name From Loan (2) Where Clause:- Where Clause esa Relation ls lacaf/kr Conditions dks fy[kk tkrk gSaA Example:- ;fn Loan Relation esa ls mu Records dks Select djuk gSa tks delhi branch ls gSa o ftudk Amount 3000 ls vf/kd gSa rks blds fy;s fuEu Query Perform dh tk,xh%&

select loan_no. from Loan where branch_name = ‘Delhi’ and amount>3000



Where Clause ds :i Relation Operator (>, <, >, <, =, #) vkfn dks rFkk Logical Operator (and, or, not) dks Hkh mi;ksx esa fy;k tkrk gSaA Codd’s Rules:- E.F. Ted Codd’s ds }kjk Functional Database Management System ij Rules fufeZr fd;s x;s gSa tks fuEu gSa%&

(1) Relation Database Management:- RDBMS }kjk flQZ Information dh Relational Capabilities dks Manage fd;k tkrk gSaA

(2) Information Representation:- lHkh Information ftls Relation Database }kj iznf’kZr fd;k tkrk gSa mUgsa Data Item Values ds :i eas Store fd;k tkrk gSa ;s lHkh Data Items Table esa Store jgrs gSaA

(3) Logical Accessibility:- gj Relation ds Data Item dh Value dks Access djus ds fy;s table dk uke] Column o Primary Key Value dks define fd;k tkrk gSaA

(4) Representation of Null Values:- DBMS ds }kjk Null Values dks Hkh iznf’kZr fd;k tkrk gSaA Numeric Values ds fy;s Null Value 0 ;k dksbZ vU; digit gksrk gSa o Character ds fy;s Null Value Blank Space ;k dksbZ vU; Character Value gksrh gSaA

(5) Data Language:- RDBMS ds }kjk Data o Database Accessing Language dh ifjHkkf"kr fd;k tkrk gSaA (6) Insert, Update & Delete:- fdlh Hkh Operation ds }kjk Database esa Values dks Insert Updates o

Delete fd;k tk ldrk gSaA (7) Physical data Independence:- tc Physical Storage Representation ;k Access Methods dks

Change fd;k tkrk gSa rks Application Programs esa Change dh vko’;drk ugha gksrhA (8) Integrity Constraints:- DBMS esa Data Languages ds }kjk Entity o Referential Integrity dks

define fd;k x;k gSaA (9) Data Distribution:- DBMS ds fy;s ftu Database Languages dks cuk;k x;k gSa muls distribute

Database ij Change fd;s tk ldrs gSaA (10) No Subversion:- DBMS User ds }kjk ,d leku flQZ ,d Row ij Operation Perform fd;k tkrk gSa

ftlls Entity o Referential Integrity Constraints dh Hkh lqj{kk gksrh gSaA

JOINS Natural Join:- tc fdlh Query ij Cartesian Product Perform fd;k tkrk gSa rks bl Cartesian Product Perform fd;k tkrk gSa rks bl Product ds Result ds ckn ml ij Selection Condition dks Apply fd;k tkrk gSaA tSls%& ;fn Bank ds mu lHkh Customers dh List dks Display djuk gSa ftUgksaus Bank ls Loan ys j[kk gSa o lHkh Loan No. o Loan Amount dks Hkh Display djuk gSa rks blds fy, lcls igys Borrower o Loan Relation ij Cartesian Product Perform fd;k tk,xk ckn esa Same Loan Number okys Tuples dks Select fd;k tk,xkA blds fy;s fuEu Query Perform dh tk,xh%& π customer_name, Loan_number, Amount (borrower) Loan_number = Loan, Loan_number (borrower X Loan) bl leL;k dks nwj djus ds fy, Natural Join Operation Perform fd;k tkrk gSa ftlesa Selection o Cartesian Product dks ,d Operation esa ifjofrZr dj fn;k tkrk gSaA bls Symbol }kjk iznf’kZr fd;k tkrk gSaA π customer_name, Loan_number, cannot (borrower Loan) Outer Join:- Outer Join Operation Join Operation dk Extension gSa ftlesa Missing Information dks Hkh Display fd;k tkrk gSaA tSls%& ;fn gekjs ikl nks Relation gSa%& Employee (Employee_name, Street, city) Works (Employee_name, branch_name, Salary) vc ;fn bu ij Natural Join Operation Perform fd;k tkrk gSa] lk nksuks Relation esa ls Employee name ds vk/kkj ij Selection fd;k tk,xkA ;fn ,d Relation esa ,d vU; Employee_name gSa tks nwljs esa ugha gSa rks ml Information dks Display ugha fd;k tk,xkA



bl Loss Of Information dks Explain djus ds fy;s o Remove djus ds fy;s Outer Join Operation & Perform fd;k tkrk gSaA Outer Join Operation dks 3 Hkkxksa esa ck¡Vk x;k gSa%&

(1) Left Outer Join (2) Right Outer Join (3) Full Outer Join (1) Left Outer Join esa left Relation ds mu lHkh Tuples dks Display fd;k tkrk gSa tks Right Relation dks

match ugha gksrsA vr% tks Tuples Right Relation esa ugha gSa ogk¡ ij Null Values dks Insert fd;k tkrk gSaA vr% Left Relation dh lkjh Information izkIr gksrh gSaA

(2) Right Outer Join esa Right Relation ds mu lHkh Tuples dks Display fd;k tkrk gSa tks Left Relation ls Match ugha gksrsA vr% tks Tuples Left Relation esa ugha gSa ogk¡ ij Null Values dks Insert dj fn;k tkrk gSaA vr% Right Relation dh lkjh Information izkIr gksrh gSaA

(3) Full Outer Join esa Right o Left Relation ds Unmatched Operation o tuples dks 'kkfey dj Display fd;k tkrk gSa o Null Value Insert dj nh tkrh gSaA



UNIT-III Functional Dependencies %&

(1) bl dependency ds }kjk Bad Database Design dks Good Database Design esa ifjofrZr fd;k tkrk gSaA (2) Functional Dependency ,d ,slh Key gSa ftlds }kjk Database ij Generalization fd;k tkrk gSaA (3) fdlh Hkh Relation esa Attribute A, Attribute B ij rHkh fuHkZj djrk gSa tc B dh gj Value ds fy;s A dh

Exactiy ,d Value gksA (4) Attribute B, ftl ij Attribute A depend djrk gSa mls determinant dgk tkrk gSaA (5) Functional Dependency dks nks izdkj ls mi;ksx fy;k tk ldrk gSa%&

(1) Relation (table) dh lHkh vko’;d Functional dependency dks Check djukA (2) Relations in dqN vko’;d Limitations ds fy;s Hkh Functional dependency dks mi;ksx esa fy;k

tkrk gSaA Example:- ,d Relation Employee ftlesa fuEu Attributes dks 'kkfey fd;k x;k gSaA

Employee = {Ecode, Name, City} EMPLOYEE

Ecode Name City E1 A1 Delhi E2 A2 Calcutta E3 A3 Madras

mijksDr Employee Table esa gj Ecode ds fy;s Name dh Exact ,d Value ds fy;s gSaA vr% ;g dgk tk ldrk gSa fd Name Ecode ij Functionally dependent gSaA vr% Ecode dks determinant dgk tkrk gSaA vr% Ecode ds vk/kkj in Name o City nksuksa dks Access fd;k tk ldrk gSaA

Normalization dk iwjk Concept Functional dependency ij fuHkZj djrk gSaA Relational Database Design dh dfe;k¡ fuEu gSa%& Bad Database design esa fuEu dfe;ksa dks iznf’kZr fd;k tkrk gS%&

(1) Repetetion of Information (2) Information dks dHkh&2 iwjh rjg ls iznf’kZr ugha fd;k tkrkA (3) Database esa Insertion ds le; vkus okyh leL;k gSA (4) Database esa deletion ds le; vkus okyh Problem:-

bu lHkh leL;kvksa dks Database ls gVkus ds fy;s Relation dks NksVs&2 Hkkxksa esa ck¡Vdj u;s Relation cuk;s tkrs gSa ftlls fdlh Hkh izdkj dk Information Loss u gkaA bl izdkj dh fof/k;ksa dks decomposition Tecniques dgk tkrk gSa ;k Loss-less Join dgk tkrk gSa ;k Lossy decomposition dgk tkrk gSaA tSls ,d Relation R gSa tc Database Anomalies ¼dfe;ksa½ dks nwj djus ds fy;s NksVs&2 Hkkxksa esa ck¡Vk tkrk gSa rks%&

R = {r1 U r2 U r3 ………. U rn} ;k

R = {r1 U r2 U r3 ………. U rn} vr% tc lHkh decomposed Relation dks feyk;k tkrk gSa rks iqu% Relation R curk gSa o fdlh Hkh Information dk loss ugha gksrk gSaA UNIVERSAL RELATION APPROACH:- Database Design ds le; Single Relation dks ysdj mlesa lHkh vko’;d Attributes dks mi;ksx esa ys fy;k tkrk gSaA rFkk ckn esa bl Relation dks NksVs&2 Hkkxksa esa (Relation) esa foHkDr dj fn;k tkrk gSaA Decomposition dk eq[; mn~ns’; Information Loss dks u gksus nsuk gSaA

Example:- ,d Loan Relation esa fuEu Attributes dks ifjHkkf"kr fd;k x;k gSa%& Loan:- (i) Branch Name, Loan Number (ii) Loan_number, Amount (iii) Loan_number, Customer Name



mijksDr rhu decomposed Relation gSaA blesa ls (i) Relation esa Loan Amount dks Store ugha fd;k x;k gSa rks bl izdkj ds Records dks danling Records o tuples dks dangling Tuples dgk tkrk gSa D;ksafd tc Hkh bu rhuksa Tables dks Join djds data Access fd;k tk,xk rc Record Information v/kwjh izkIr gksxh D;ksafd Loan Amount dks Insert ugha fd;k x;k gSaA blds fy;s Record Information dks [kkyh u j[kdj Null Value dks Insert dj fn;k tkrk gSa rFkk bl izdkj ds Relations dks Universal Relation dgk tkrk gSaA ¼;wfuolZy½ vr% Null Value dks fcuk Database esa fdlh Hkh Unknown Value dks Insert ugha fd;k tkrkA NORMALIZATION:- Normalization ,d oSKkfud fof/k gSa ftlds }kjk Complex Table Structure dks Simple Table Structure esa ifjofrZr fd;k tkrk gSaA Table esa ls Redundancy dks de djus o Database Inconsistency dks gVkus ds fy;s dqN Rules dks Follow dj ukeZykbts’ku fd;k tkrk gSaA blesa ;g Hkh /;ku j[kk tkrk gSa fd Normalization ds le; Information dk dksbZ Loss uk gksA Normalization ds cgqr ls ykHk gS] ftlds }kjk Fast Sorting, Indexing o Clustering dh tk ldrh gSa o ;g Table Structure dks Simple cukus dk dk;Z Hkh djrk gSaA fdlh Hkh Database Design dks vPNk cukus ds fy;s fuEu Rules dks Follow fd;k tkrk gSa%&

(1) gj Table esa ,d Identifier dk gksuk vko’;d gSaA (2) gj Table esa Singal Type dh Entity dks Store fd;k tkuk pkfg;sA (3) Null Value dks de ls de Store fd;k tkuk pfg;sA (4) Values dk Repetition ¼iqujko`fr½ Hkh de ls de gksuk pkfg;sA

Normalization Concept dks Apply djus ds fy;s vyx&2 Normal Forms dks mi;ksx esa fy;k tkrk gSaA Vscy ges’kk fdlh u fdlh Normal Form esa gksrh gSaA eq[;r% mi;ksx esa yh tkus okyh Normal Forms fuEu gS%&

(1) First Normal Form (1NF) (2) Second Normal Form (2NF) (3) Third Normal Form (3NF) (4) Fourth Normal Form (4NF) (5) Boyce Coded Normal Form (BCNF) (6) Fifth Normal Form (5NF)

(1) First Normal Form (1NF):- fdlh Hkh Vscy dks 1NF esa rHkh dgk tk ldrk gSa tc Vscy dh gj Cell esa ,d Value gksA Example:- ,d Relation Employee esa fuEu Attributes dks Insert fd;k x;k gSa%& Ecode:- (Ecode, Dept, Proj Code)

Employee Ecode Dept Proj Code E 101 Finance P27

P51 P20

E 303 Purchase P27 P22

E 709 Sales P51 P27

mijksDr Vscy esa lHkh Cell Value dks Insert ugha fd;k x;k gSa ijUrq Projcode Values ,d gh Cell esa ,d ls vf/kd gSaA vr% ;g Table Normalizaed Form eas ugha gSa] vr% bl ij 1NF ds Rule dks Apply fd;k tk,xk rFkk Table fuEu izdkj cusxh%&



Employee

Ecode Dept Proj Code E 101 Finance P27 E 101 Finance P51 E 101 Finance P20 E 303 Purchase P27 E 303 Purchase P22 E 709 Sales P51 E 709 Sales P27

mijksDr Table 1NF esa gSaA (2) Second Normal Form (2NF):- dksbZ Hkh Table 2NF esa rHkh gksxh tc og 1NF esa gks rFkk Row dk gj Attribute Primary Key in Functionally Dependent gksuk pkfg;s u fd Primary dh ds fdlh Part ijA vr% fdlh Hkh Vscy dks 2NF esa cnyus ds fy;s fuEu fu;eksa dks Follow fd;k tkrk gSa%&

(1) mu Attributes dks Find dj mUgsa gVkuk tks Primary Key dks Part ¼Hkkx½ in dependent gksA mUgsa vyx Vscy esa Store djukA

(2) vU; cps Attributes dks ,d lkFk ,d Vscy esa j[kukA Example:- Project Table esa fuEu Attributes dks 'kkfey fd;k x;k gSa%& Project:- (Ecode, Pcode, Dept, Hours}

PROJECT

Ecode Pcode Dept Hours E1 P27 Finance 90 E2 P27 Pruchase 5 E3 P51 Sales 7 E1 P51 Finance 100 E1 P20 Finance 50 E3 P27 Sales 30

mijksDr Table 2NF esa ugha gSa ;k Table esa fuEu leL;k gSa%& (1) fdlh Hkh Employee ds department dh rc rd Store ugha fd;k tk ldrk tc rd fd mls dksbZ Project u

fn;k x;k gksA (2) Code o Dept. ckj&2 Repeat gks jgs gSa vr% Information Updation esa Hkh Problems vk,xhA ftlls

Inconsistency c<+sxhA (3) ;fn dksbZ Employee Project Complete dj ysrk gSa rks Employee dk Record ;k Project Delete djus in

iwjk Record Delete gks tk,xkA mijksDr Table Non Key Attribute ¼tks Primary Key esa 'kkfey ugha gSa½ iwjh Primary Key (Key Attribute) in Functionally Depend gksus pkfg;sA

(1) lcls igys Dept. (Non-Key Attribute) dh dependency dks pSd fd;k tk,xkA Ecode ds fy;s Dept dh Value ,d ges’kk ,d gS vr% Dept, Ecode in Functionally Dependent gSaA ijUrq Proj Code ds fy;s Dept. dh Value ,d ls vf/kd gSa vr% Dept Pcode in Functionally dependent ugha gSaA vr% Ecode+Pcode dks 'kkfey (Whole Key) djus in Hkh Dept Functionally Dependent ugha gSa vr% dept

Ecode in rks Functionally dependent gSa ijUrq Pcode in ugha vr% Part of the Primary Key ij Dept ij ughaA (2) Hours (Non-Key Attribute) dh dependency dks Check djuk gSaA Ecode ds fy;s Hours dh ,d ls

T;knk Value gS vr% Hours, Ecode in Functonally Dependent ugha gSaA gj Project ds fy;s ;k Pcode ds fy;s Hkh Hours dh ,d ls vf/kd Values gSa vr% Hours, Pcode ij Hkh Functionally Dependent ugha gSaA ijUrq tc iw.kZr% Primary Key dh ckr dh tkrh gSa rks Hours (Pcode+Ecode) in Functionally dependent gSaA



vr% Dept ,d ,slk Non-Key Attribute gSa tks Relation dh Primary Key in Functionally Dependent ugha gSaA vr% ml Non Key o Key Attribute ftl ij Depend djrh gSa nksuks dks Table ls vyx dj fn;k tk,xkA

(1) Dept = {Ecode, Dept} (2) Project = {Ecode, Pcode, Hours}

(3) Third Normal Form (3NF):- dksbZ Hkh Relation 3NF esa rHkh dgykrk gSa t cog Realtion 2NF esa gks rFkk gj Non-Key Attribute flQZ vkSj flQZ Primary Key ij dependent gksA

vr% fdlh Hkh Table dks 3NF esa cnyus ds fy;s fuEu Rules dks Follow fd;k tkrk gS%& (1) mu Non Key Attributes dks <w¡<dj Rename djuk tks Primary Key ds vykok ,d nwljs ij Hkh depend

djrk gksA (2) mu lHkh Attributes dks ,df=r djukA

Example:- ,d Relation Employee esa fuEu Attributes dks 'kkfey fd;k x;k gSa%& Employee = {Ecode, Dept, Dept Head}

EMPLOYEE

Ecode Dept Dept Head E1 Sales E705 E2 Pruchase E302 E3 Purchase E302 E4 Sales E705 E5 Finance E301

mijksDr Relation esa lHkh izdkj dh Anomalies (Problems) mifLFkr gS%& (1) Updation (2) Deletion

vr% Table dks 3NF ds fy;s pSd djuk gksxkA bl Vscy ds fy;s Primary Key – Ecode gSaA (1) gj Ecode dh Value ds fy;s Dept dh ,d Value gSa vr% Dept, Ecode in Functionally dependent gSaA (2) blh izdkj gj Ecode ds fy;s DeptHead Hkh ,d nwljs in Functionally Dependent gSaA vr% bu nksuks

Attributes dks vyx Table esa decompose dj fn;k tk,xkA vr% ,d Relation nks Parts esa divide gks tk,xk%&

(1) Employee = {Ecode, Dept} (2) Department = {Dept, Deptifead}

(4) BOYCE-Codd Normal form (BCNF):- dHkh&dHkh 3NF dh ifjHkk"k dqN Tables ds fy;s mi;qDr ugha gksrh tSls%& (1) tc Vscy esa ,d ls vf/kd Candidate Keys gksA (2) tc Multiple Candidate Keys Composite gksA (3) tc Multiple Candidate Key esa ,d Key Attribute Common gksA

bu lHkh dkj.kksa ls ubZ Normal Form develop dh xbZ ftls BCNF dgk tkrk gSaA

PROJECT

Ecode Name Pcode Hours E1 A P2 48 E2 B P5 100 E3 C P6 15 E4 D P2 250 E4 D P5 75 E1 A P5 40



bl Table ds fy;s Primary Key Ecode Pcode gSa ijUrq name o Pcode dks Hkh Primary Key pquk tk ldrk gSa] vr% ;g Candidate Key gSaA mijksDr Table esa fuEu lwpuk,¡ izkIr gksrh gSa%& (1) Table esa Multiple Candidate Key gS%& (1) Ecode + Pcode (2) Name + Pcode (1) Candidate Keys Composite gSaA (2) lHkh Condidate Keys esa Pcode ,d ,slk Attribute gSa tks Common gSaA vr% bl Condition esa BCNF dks Apply fd;k tkuk pkfg;s ijUrq lkFk Functional deptendency dks Hkh check fd;k tkrk gSa%&

(1) Hours Primary Key in Functionally Dependent gSaA (2) Hours, Name + Pcode ij Hkh Functionally dependent gSaA (3) Name, Ecode ij Hkh Functionally Dependent gSaA (4) Ecode Hkh Name ij Functionally Dependent gSaA

vr% BCNF ds fy;s fuEu Rules dks Follow fd;k tk,xk%&

(1) Overlapped Condidate Key dks <w¡<dj mls Remove djuk o og ftl in dependent gSa mlds lkFk vyx Table eas decompose djukA

(2) vU; Attributes dks ,d lkFk ,d Table esa j[kukA vr% Name o Ecode dks vyx Table esa j[kk tk,xk%&

(1) Employee:- Ecode Name (2) Project:- Ecode Pcode Hours

(4) Fourth Normal Form (4NF):- lHkh Normal Form (BCNF) rd Apply djus ij Hkh Relation esa tks Main Problem jg tkrh gSa og gSa Information dk Repeat gksukA

tc ,d gh Attribute ds fy;s fdlh nwljs Attribute dh ,d ls vf/kd Values gks rks bl izdkj dh leL;k dks nwj djus ds fy;s Multivalued dependency dks Apply fd;k4 tkrk gSaA ftl Normal Form esa Multivalue dependency dks Consider fd;k tkrk gSa mls 4NF dgk tkrk gSaA

5NF (PJNF):- tc Relation esa Join dependency dks Consider fd;k tkrk gSa rks bl izdkj dh Normal Form Project Join Normal Form ;k Fiften Normal Form dgykrh gSaA



UNIT-IV INDEXING & HASHING

fdlh Book ;k Card Catalog dh rjg gh Database ds Indexes dks Maintain fd;k tkrk gSaA mnk% ;fn Account Number ds vk/kkj ij Account Table ls Record Add djuk gks rks Database System] Index esa ls Disk Block <¡w<dj Record dks Main Memory esa ykrk gSaA

;fn Index Hkh Sorted gks rks Record dks <w¡<us esa le; de yxrk gSaA eq[;r% nks izdkj Index dks mi;ksx esa fy;k tkrk gSa%& (1) Ordered Index:- ;g Database dh Sorted Values ij fuHkZj djrh gSaA (2) Hash Index:- blesa Values dks Bucket esa Uniformly Store fd;k tkrk gSaA Bucket esa fdlh Value dks

Store fd;k tkrk gSa blds fy;s ,d Function dks mi;ksx esa fy;k tkrk gSa ftls Hash Function dgk tkrk gSaA nksuks izdkj dh Indexing ds fy;s cgqr lh fof/k;k¡ viukbZ xbZ gSa] ijUrq dksbZ Hkh rduhd mi;qDr ugha gSaA gj

Technique dks eq[;r% fuEu Factors ds }kjk ekik tkrk gSa%& (1) Access Types:- blesa Records dks fdlh Attribute ls Find fd;k tkrk gSa rFkk lkFk mu Records dks Hkh

Find fd;k tk ldrk gSa tks Specific Range esa vkrk gksA (2) Access Time:- fdlh MkVk vkbVe ;k Set on item dks <w¡<us esa yxk le;A (3) Insertion Time:- fdlh u;s Date Item dks Database esa Insert djus esa yxk le;A (4) Deletion Time:- fdlh MkVk vkbVe dks Database ls Delete djus esa yxk le;A (5) Space Overhead:- Index Structure ds }kjk vfrfjDr mi;ksx esa fy;k x;k LislA

og Attribute ftlds }kjk fdlh QkbZy ds Record dks Search fd;k tkrk gSa] Search Key dgykrh gSaA Ordered Indexes:- Records dh Fast Searching ds fy;s Index Structure dks mi;ksx esa fy;k tkrk gSaA fdlh Book ds Index dh rjg gh Ordered Index esa Hkh Search Key Values dks Sorted Order esa ifjHkkf"kr fd;k tkrk gSaA bl izdkj gh QkbZy dks vyx&2 Search Key ds vk/kkj ij Index fd;k tk ldrk gSaA ;fn fdlh QkbZy esa Records dks Sequentially j[kk x;k gSa rks Primary Index esa Search Key Values dks Hkh Sequentially Define fd;k tk,xkA Primary Index dks Clustering Index Hkh dgk tkrk gSaA Primary Index esa eq[;r% Search Key Primary Key gh gksrh gSaA ijUrq ,slk vko’;d ugha gSaA Sequential Order ds vykok ;fn fdlh vU; order dks use esa ysdj Search Key dks define fd;k x;k gSa] rks ;g Index Secondary Index dgykrk gSaA (1) Primary Index:- lHkh Files dks fdlh Search Key ds vk/kkj ij Sequentially Ordered fd;k tkrk gSaA os Files ftlesa Search Key Primary Index ds Concept ij dk;Z djrh gSa mUgsa Index Sequential File dgk tkrk gSaA

A-No. BRANCH Amount A-217 DELHI 750 A-101 DELHI 500 A-110 DELHI 600 A-215 HYDERABAD 700 A-102 HYDERABAD 400 A-201 HYDERABAD 900 A-218 MUMBAI 700 A-222 MUMBAI 700 A-305 MUMBAI 350

SEQUENTIAL FILE

DENSE AND SPARSE INDEX:- Ordered Index dks eq[;r% nks Hkkxksa esa ck¡Vk x;k gS%& (1) DENSE INDEX (2) SPARSE INDEX

DELHI HYDERABAD MUMBAI



(1) DENSE INDEX:- tc QkbZy dh gj Search Key Value ds fy;s Index Record Maintain fd;s tkrs gSa rks bl izdkj ds Index dks dense Index dgk tkrk gSaA Sparse Index dh vis{kk dense Index ls Fast Searching Perform dh tk ldrh gSaA Index Record esa Search Key Value rFkk Search Key ds First Data Record ds Pointer dks j[kk tkrk gSaA

A-No. BRANCH Amount A-217 BIKANER 750 A-101 BIKANER 500 A-110 BIKANER 600 A-215 CALCUTTA 200 A-102 CALCUTTA 400 A-201 DELHI 250 A-218 MADRAS 400

DENSE INDEX

(2) Sparse Index:- ;s Index-Record dqN Serach Key Values dks gh Store djrk gSaA bl izdkj ds Index ls Record dks Search djus ds fy;s Index Table ls dh mlls cM+h ;k NksVh Value dks Search dj Sequentially Records dks Search fd;k tkrk gSaA

Sparse Index dh vis{kk Dense Index ls fast searching perform dh tkrh gSA

A-No. BRANCH Amount A-217 BIKANER 750 A-101 CALCUTTA 500 A-110 CALCUTTA 600 A-215 MADRAS 700 A-102 PILANI 400 A-201 PILANI 900 A-218 PILANI 700 A-222 RURKI 100 A-350 RURKI 350

SPARSE INDEX

MULTILEVEL INDICES:- ;fn Sparse Index dks mi;ksx esa ysrs gSa rks Records ij Processing ds fy;s Index Hkh cgqr cM+k gks tkrk gSaA tSls ;fn QkbZy esa 10,00,00 Records gSa rFkk gj Block esa 10 Records dks Store fd;k x;k gSa o ;fn gj Block ds fy;s ,d Index Record cuk;k x;k gS rks Hkh Index esa 10,000 Records dks LVksj djuk iM+sxkA Index Records Data Records ls NksVs gksrs gSa vr% ;g eku ysrs gSa fd ,d Block esa 100 Records dks j[kk x;k gSaA vr% Index dks 100 blocks dh vko’;drk gksxh rFkk bu Indexes dks Disk ij Sequential File ds :i esa Store fd;k tkrk gSaA ;fn Index dh lkbZt NksVh gks o mls Main Memory esa j[kk tk, rks Indexing }kjk Records Searchdjus esa de le; yxsxkA o ;fn Index cM+k gS rks mls Disk ij j[kk tk,xk ftlls Disk Block Read djus esa le; vf/kd yxsxkA vr% blds fy;s Binary Search dks mi;ksx esa fy;k tkrk gSaA vr% bl leL;k dks nwj djus ds fy;s Primary Index ij iqu% Sparse Index cuk;k tkrk gSaA ftlls File ij nks Index Create gksrs gSa%&

(1) Inner Index (2) Outer Index

BIKANER CALCUTTA DELHI MADRAS

BIKANER MADRAS RURKI



bl izdkj tc Indexing ds fy;s nks levels dks Create fd;k tkrk gSa o muesa ls fdlh vko’;d Block dks gh Read fd;k tkrk gSa] rks bl izdkj dh Indexing dks Two-level Indexing dgrs gSaA blesa Outer Index dks Main Memory esa j[kk tkrk gSaA ;fn Outer Index cM+k gks rks mldh iqu% Indexing dj nh tkrh gSa o lcls var esa cus Index dks Main Memory esa j[kk tkrk gSaA bl izdkj dh Indexing dks Multi-lelvel Indexing dgk tkrk gSaA

SECONDARY INDEX

tc Multilevel Index dks mi;ksx esa fy;k tkrk gSa rks, Index level dks fuEu izdkj ifjHkkf"kr fd;k tkrk gSaA (1) Inner Index (Primary Index) (2) Outer Index (Secondary Index)

Secondary Index ges’kk Dense gksuk pkfg;sA ftlesa gj Search Key Value dh Index Entry dks j[kk tkrk gSa o lkFk lkFk gj Record Pointer dks Hkh j[kk tkrk gSaA Primary Index Sparse Index gks ldrk gSa ftlesa dqN Search Key Values dks gh LVksj fd;k tkrk gSaA

Secondary Index ds }kjk Query Performance dks lq/kkjk tkrk gSa] ftlesa Primary Index dh Search Key Values dks mi;ksx esa fy;k tkrk gSaA

A-No. BRANCH Amount A-101 DELHI 500 A-217 BOMBAY 750 A-110 DELHI 600 A-215 MADRAS 700 A-102 PILANI 400 A-201 PILANI 900 A-218 RURKI 700 A-222 RAJKOT 700

SECONDARY INDEX B+ TREE INDEX FILES:- Index Sequetial file Organization dh eq[; gkuh ;g gSa fd tSls&2 File esa Records c<+rs gSa oSls&2 bl File Organization dk Performance level de gksrk tkrk gSaA vr% blds fy;s B+ Tree Index Structure dks mi;ksx esa fy;k tkrk gSa] ftlls QkbZy esa Records dk Insertion o deletion vklkuh ls fd;k tk ldrk gSaA B+ Tree Index ,d Balanced Tree dh Form esa jgrk gSa ftlesa Root ls Leaf rd gj Path dh yEckbZ lkeku gksrh gSaA

Data Block 0

Data Block 1

2

(Inner Index) On Disk

(Outer Index) Main Memory



B+ Tree Structure Insertion o deletion mifjO;; dks rks Remove dj nsrk gSa ijUrq Space Overhead dks Add dj nsrk gSa ijUrq ;g mifjO;; vU; mifjO;;ksa ls vf/kd mi;qDr gSaA D;ksafd blls File Organization dk Performance Level c<+ tkrk gSaA B+ Tree Structure dks Index ds lkFk lkFk File Record ds Organizer ds :i esa mi;ksx esa fy;k tkrk gSaA blesa B+ tree ds leaf Nodes esa Pointers ds LFkku ij Record dks Store fd;k tkrk gSaA

B+ Tree File Organization

B+ Tree esa leaf node esa nonleaf Node ds Point ls] ,d de Records dks j[kk tkrk gSaA B+ Tree Index o B+ Tree File Organization nksuksa esa Insertion o deletion ,d gh izdkj ls fd;k tkrk gSaA ;fn fdlh B+ Tree dks ifjHkkf"kr fd;k tk, rks fuEu ckrksa dks /;ku esa j[kuk vko’;d gSa%& (1) ;fn n dh Value nh xbZ gS rks mlesa N-1 Value o N Pointers dks j[kk tk,xk tSls%& ;fn N=3 gks o Search Key Branch Name gSa rks ,d Node esa N-1 Values rFkk N= 3 Pointers dks Store fd;k tk,xkA B-Tree Index Files:- B-Tree Index fcYdqy B+ Tree Index dh rjg gh gksrh gSaA nksuksa Index Files esa eq[; vUrj ;g gSa fd B-Tree Index esa Search Key Values dh Redundaut (Duplicate) Values dks Remove ¼nwj½ dj fn;k tkrk gSaA B Tree ds }kjk Search Key Values dks ,d ckj gh iznf’kZr fd;k tkrk gSaA leaf node fcYdqy B+Trees dh rjg gksrh gSaA

I

C F K M

A,4 B,8 C1 D5 E4 F7 G3 H3

I4 IB

K1 L6 M4 H8 P6

Val1 Val 2

1 Pointer 2nd Pointer 3rd Pointer

Bombay y Delhi z

A-212 Bombay A-101 Delhi A-110 Delhi

Leaf Node



Static Hashing:- Sequential File Organization dh ,d deh ;g gSa fd MkVk dks Search djus ds fy;s Index Structure dks Access fd;k tkrk gSa o blds fy;s Binary Search dks mi;ksx esa fy;k tkrk gSaA ftlls vf/kd Input/Output Operations dks Perform djuk iM+rk gSaA ijUrq tc File Organization, Hashing rduhd in fuHkZj djrh gSa rks blls vf/kd I/O Operation dh vko’;drk ugha gksrhA Hashing ds }kjk Hkh Index dks cuk;k tkrk gSaA Hash File Organization:- bl Organization esa Record dh Search Key Value ij ,d Function ¼QaD’ku½ Perform fd;k tkrk gSaA ftlls vko’;d Disk Block ds vko’;d Record dks vklkuh ls Search dj fy;k tkrk gSaA Hashing ds vUrxZr Bucket Keyword dks mi;ksx esa fy;k tkrk gSaA ftlesa ,d ;k ,d ls vf/kd Records dks Store dj j[kk tkrk gSaA vr% Bucket ,d Disk block tSlk gSaA ysfdu ;g ,d Disk Block ls NksVk ;k cM+k gks ldrk gSaA ekuk K ds }kjk lHkh Search Key Values dks iznf’kZr fd;k tkrk gSa rFkk B }kjk lHkh Bucket Address dks iznf’kZr djrk gSaA Hash Function h ,d Function gSa ftlds }kjk K Search Key Values ls B Bucket ds Specific Record ij igq¡pk tkrk gSaA fdlh Record dks mldh Search Key (k1) ds lkFk Store djus ds fy, ml ij h (Hash Function) (ki) ijQkeZ fd;k tkrk gSaA tks Record ds Bucket Address dks Return djrk gSaA bl izdkj Records dks mijksDr fof/k }kjk Delete Hkh fd;k tk ldrk gSaA Hash Function:- lcls csdkj Hash Function og gSa ftlesa ,d gh Bucket esa lHkh Search Key Value dks j[kk tkrk gSaA ftlls fdlh Hkh Record dks <¡<us ds fy;s iwjh Bucket Record dks Search djuk iM+rk gksA ,d vPNk Hash Function ogh gSa ftlesa Key Values dks lHkh Bucket ,d :i esa Store fd;k tk,A vFkkZr~ lHkh Buckets esa ,d leku Records dks Store fd;k tk,A vr% gj Bucket esa Records dh ek=k leku gksrh gSaA vr% Design time ij User ugha tkurk fd fdl Search Key Values dks File esa dgk¡ LVksj fd;k x;k gSaA vr% Search Key Values dks Bucket esa j[kus ds fy;s Hash Function dks mi;ksx fd;k tkrk gSaA Buckets esa Search key Values dk distribution (forj.k) fuEu izdkj fd;k tkrk gSa%&

(1) forj.k Uniform gksuk pkfg, ¼leku½ (2) forj.k Random ¼vleku½ Hkh gks ldrk gSaA

Bucket Overflow:- tc Record dks Insert fd;k tkrk gSa rks Bucket esa ml Record ds fy;s Space Hkh dh tkrh gSaA ijUrq ;fn Bucket esa vko’;d Space ugha gS] rks Bucket Overflow dh ifjfLFkfr mRiUu gksrh gSaA Bucket Overflow cgqr ls dkj.kksa ls mRiUu gksrk gSa tks fuEu gSa%& (1) Insufficient Buckets:- ¼tc iw.kZ :i ls Buckets miyC/k uk gks½%& Buckets (nB) ges’kk nr/fr ls vf/kd gksuh pkfg;sA ;gk¡ nr- lHkh Records ftUgsa Store djuk gksA fr- ,d Bucket esa fit gksus okys Records dh la[;k vr% nB tc nr/fr ls vf/kd gksxk rHkh Bucket Overflow dh leL;k dks gVk;k tk ldrk gSaA (2) Skew ¼Ld;w½%& dqN Buckets esa vU; Bucket dh vis{kk T;knk Records dks Store dj fn;k tkrk gSa tcfd nwljh Buckets esa Space cpk gksrk gSaA bl izdkj dh Condition dks Skew dgk tkrk gSaA Skew eq[;r% nks dkj.kksa ls mRiUu gksrh gSa%& ¼1½ tc cgqr ls Records dh ,d Search dh gksA ¼2½ tc Hash Function }kjk Search Keys dk vleku forj.k fd;k tk,A Overflow dks jksdus ds fy;s ;g vko’;d gSa fd vU; Buckets dks Allocate dj fn;k tk, Bucket Overflow dks Overflow Bucket }kjk Hkh nwj fd;k tk ldrk gSaA tSls%& ;fn Record dks Bucket b esa Store djuk gSa o b igys ls iwjh gks pqdh gSa rks System }kjk b dks Oveflow Bucket ns nh tkrh gSa rFkk Record dks Overflow Bucket esa Insert dj fn;k tkrk gSaA ;fn Overflow Bucket Hkh Full gks tk, rks System }kjk vU; Overflow Bucket Provide djok nh tkrh gSaA bl izdkj ;g Øe pyrk jgrk gSaA lHkh Overflow Buckets dks ml Bucket ds lkFk Link list dh rjg Store dj fn;k tkrk gSaA bl izdkj dh List dks Overflow Chaining dgk tkrk gSaA



HASH INDICES:- Hasing dks File Organization ds lkFk&lkFk Index-Structure ds fy;s Hkh mi;ksx esa fy;k tk ldrk gSaA hash index ds }kjk Search Key dks mlds Pointer ds lkFk Hash File Structure esa Store fd;k tkrk gSaA Dynamic Hashing:- tc Bucket b esa Fix Address dks j[kk tkrk gSaA Static Hashing ds le; dHkh dHkh Serious Problems Occur gks tkrh gSaA vr% bl izdkj dh Condition Occur uk gks blds fy;s fuEu Option dks mi;ksx esa fy;k tkrk gSa%&

(1) Current File Size ds vk?kkj ij Hash Function dks pquuk (2) ml Hash Function dks pquuk tks Current File ds lkFk lkFk vfrfjDr Space dks Hkh Consider djs ftlls

Performance Hkh c<rh gSa ijUrq Space vf/kd Waste gksrk gSaA (3) File Growth ¼c<us½ ds lkFk lkFk Hash Structure dks Hkh iqu% Reorganize djuk ;g Operation time

Consuming rks gSaA ijUrq Accessing ds fy;s vko’;d Hkh gSaA Dynamic Hashing fof/k;ksa ds }kjk Hash Function dks Database ds c<us ;k de gksus ds lkFk&2 ifjofrZr

fd;k tk ldrk gSaA vFkkZr~ Hash Function Database dh Growth dks rks ugha cny ldrk ijUrq Growth ds lkFk lkFk Hash Function dks ifjofrZr fd;k tk ldrk gSaA

INDEX DEFINITION IN SQL:- Index Database dh Efficient Processing ds fy;s vko’;d gksrs gSa ftlesa Transaction dks Update fd;k tkrk gSaA o mu ij Queries Hkh Perform dh tkrh gSaA SQL esa Index Create djus ds fy;s Create Index Command dks mi;ksx esa fy;k tkrk gSaA

Syntax:- Create index <index_name> on <relation_name> (<attributes>) Attributes esa mu Columns dks 'kkfey fd;k tkrk gSa ftu ij Index

Create djuk gksA

Bucket 0

Bucket 1

Bucket 2 Overflow Buckets for Bucket 1



UNIT-V FALIURE CLASSIFICATION:- (System esa gksus okys Faliure ds Hkkx):- System esa dbZ izdkj ds Faliures gksrs gSaA ijUrq lcls Simple Faliure og gSa ftlls fdlh Hkh izdkj dk Information dk Loss uk gksA ijUrq ftuesa Information Loss gksrk gSaA mlls cgqr eqf’dy ls Recovery dh tkrh gSaA eq[;r% mRiUu gksus okys Faliures fuEu gSa%& (1) Transaction Faliure:- fdlh Hkh Transaction ds Fail gksus dk dkj.k eq[; nks Errors gks ldrh gSa%&

(1) Logical Error:- tc Transaction dk Execution vf/kd le; rd fdlh Internal ¼vkarfjd½ Condition ds dkj.k Normal u jg ik, rks ;g Logical Error dgykrh gSaA tSls%& Data dk uk feyuk , Data dk Oveflow gksuk vkfnA

(2) System Error:- tc System fdlh vupkgh fLFkfr tSls dead lock dh fLFkfr esa vk tk, o blls Transaction Normal Execution esa u jgs rks bl izdkj dh Error dks System Error dgk tkrk gSaA (2) System Crash:- tc Hardware, Database Software ;k Operating System esa Error vk tk, ftlls Volatile Storage dh Information lqjf{kr uk jgs rks blls Hkh Transaction :d tkrh gSaA (3) Disk Faliure:- Head ds Crash gksus ;k Disk Block ds [kks tkus ls Data Transfer Operation ds lkFk tks Faliure mRiUu gksrk gSa mls Disk Faliure dgk tkrk gSaA

vr% MkVkcsl esa Consistency cuk, j[kus o Failure ls Recovery ds dqN Techniques ¼fof/k;k¡½ viukbZ xbZ gSa] ftUgsa Recovery Alogrithm dgk tkrk gSaA ;s eq[;r% nks izdkj ds gksrs gS%&

(1) Normal Transaction Processing ds fy;s mi;qDr Iformation dk gksuk rkfd Recovery vklkuh ls gks ldsA (2) Faliure dks Recover djrs le; Database dks Consistent o Atomic cuk, j[krs gSaA

STORAGE STRUCTURE

Storage Media dks mldh Speed {kerk ds vk/kkj in ifjHkkf"kr fd;k tkrk gSaA vr% eq[;r% Storgae nks izdkj ds gksrs gSa%& (1) Volatile Storage (2) Non-Volatile Storage

(1) Volatile Storage:- System Crash ds nkSjku Volatile Storage esa j[kh xbZ Information ugha gVrh gSaA Main

Memory ;k Cache Memory bl Storge ds eq[; mnkgj.k gSaA Volatile Storage ls MkVk dks Fastly Access fd;k tkrk gSaA

(2) Non-Volatile Storage:- System Crash dk Non-Volatile Storage ij vf/kd izHkko iM+rk gSaA Non-Volatile Storage, Volatile Storage dh vis{kk Slow gksrs gSa D;ksafd Disk ;k Tape (Non-Volatile Storage) Electro Mechanical ¼bysDVªkseSdsfudy½ gSa tcfd Volatile Storage Chips ds cus gksrs gSaA

Stable Storage:- Stable Storage esa j[kh xbZ Information dk Loss ugha gksrk gSaA

TRANSACTION MODEL Transaction izksxzke Execution dh ,d ;wfuV gSa ftlds }kjk fofHkUu Data Items dks Access o Update fd;k

tk ldrk gSaA User }kjk Execute dh tkus okyh lHkh Transactions ;k Statements dks Begin Transactoin o End Transaction ds chp j[kk tkrk gSaA vr% Database System esa fdlh Hkh Transaction dh Properties dks Follow fd;k tkuk vko’;d gSa%& (1) Atomicity ¼,VkWfeflVh½:- Transaction esa gksus okys lHkh Operations, Database esa lkQ&2 iznf’kZr gksus

vko’;d gSaA (2) Consistency:- tc Database esa dksbZ ,d Transaction Execute gks jgk gks rks nwljk Transaction Execute

ugha gksuk pkfg;s] ftlls Database esa Consistency cuh jgrh gSaA (3) Isolation:- tc Database esa Multiple Transaction Execute gks jgh gks rks igyh Transaction ds [kRe gksus

ij gh nwljh Transaction dks Execute gksuk pkfg;sA (4) Durability:- tc ,d Transaction iwjh Execute gks tk, rHkh mlls lacaf/kr Updates dks Database esa fd;k

tkuk pkfg;sA mijksDr lHkh Properties dks ACID Properties dgk tkrk gSaA



fuEu nks Operations ds }kjk dksbZ Hkh Transaction Data dks Access dj ldrk gSa%&

(1) Read (x) (2) Write (x)

Read (x) Operation ds }kjk Data item x dks Database ls Local Buffer esa Send fd;k tkrk gSaA Read – Database Local Buffer Write (x) Operation }kjk Data Item x dks Local Buffer ls iqu% Database eas Send fd;k tkrk gSaA write – Database Local Buffer

TRANSACTION STATE:- Faliure u gksus ij lHkh Transaction lQyrkiwoZd iw.kZ gks tkrs gSaA tc Trasaction lQyrkiwoZd Complete ugha gksrh rks bl izdkj dh Transaction dks Aborted Transaction dgk tkrk gSaA

Aborted Transaction }kjk fd;s x;s Changes dks tc Reject dj Transaction dks iwoZ fLFkfr esa ykuk Transaction Rollback dgykrk gSaA

tc Transaction viuk Execution iw.kZ lQyrkiwoZd dj ysrh gSa] rks mls Transaction dk Commit gksuk dgrs gSaA

vr% dksbZ Hkh Transaction fuEu esa fdlh Hkh ,d State esa gksuk pkfg;s%& (1) Active:- izkjfEHkd State, tc Transaction Execute gks jgh gksA (2) Partially Committed:- tc Transaction dk Last Statement Execute gksA (3) Failed:- tc ;g irk yx tk, fd vc Transaction dk Normal Execution laHko ughaA (4) Aborted:- tc lQyrkiwoZd Execution uk gksA (5) Committed:- tc Transaction dk Execution lQyrkiwoZd gks tk,A

LOG BASED RECOVERY:- Database esa gksus okys ifjorZuksa dks Store djus dk lcls egRoiw.kZ rjhdk Log gSaA Log esa Log Records j[ks tkrs gSaA eq[;r% Log record esa fuEu Fields dks ifjHkkf"kr fd;k x;k gSa%&

(1) Transaction Identifier:- ¼VªkWtsD’ku vkbMsfUVQk;j½ ;g Transaction dk ,d Identifier gSa ftlds }kjk Write Operation Perform fd;k tkrk gSaA

(2) Data Item:- ;g Data Item dh Disk ij fLFkfr dks iznf’kZr djrk gSaA (3) Old Value:- Data Item dh iqjkuh Value Write djus ls igys okyhA (4) New Value:- Data Item dh u;h Value (Write djus ds ckn dh Value)

Log Record dh Values dks fuEu izdkj ls iznf’kZr fd;k tkrk gSaA (1) Ti <Start> - Ti – Transaction Transaction dk Execution izkjEHk gksus ij Log Record esa Entry. (2) <Ti, xj, V1, V2 – vr% Transaction }kjk Xj data Item ij Operation Perform djukA

V1 – xj data item dh Old Value V2 – Xj Data Item dh New Value

(3) <Ti Commit> - Transaction ds Commit gksus ijA (4) <Ti Abort> - Transaction Ti ds Abort gksus ijA

;s Log Records System ;k Disk Faliure ds le; Data Recovery esa lgk;rk iznku djrs gSaA ;s Log Stable Storage esa Store fd;s tkrs gSaA Transaction dh Atomicity dks cuk, j[kus ds fy;s fuEu nks izdkj ls Log Records Maintain fd;s tk ldrs gSa%&

Log Records esa lHkh Database Transaction dk iw.kZ Record j[kk tkrk gSaA

Data Item

Data Item



(1) Deferred Database Modification:- bl rduhd esa Database Updation rHkh fd;s tkrs gSa tc Log Record Partially Commit uk gks tk,A

(2) Immediate Modification:- blesa Transaction ds Active State ds lkFk&lkFk gh Database esa Updation dj fn;s tkrs gSaA ;s Recovery Scheme nks izdkj ds Recovery Procedure ¼izkslhtj½ dks Follow djrh gSa%&

(1) Undo (Ti) – u;h Value dks iqjkuh ls Replace (2) Redo (Ti) – Data Item dh u;h Value Set djukA

Check Points:- tc System Failure gksrk gSa rc Recovery ds fy;s Log dks pSd fd;k tkrk gSa rFkk ckn esa Transaction dks Undo o Redo fd;k tkrk gSaA ijUrq Log Records ls Information Access djrs le; nks eq[; Problems vkrh gsa tks fuEu gS%&

(1) Records dks <w¡<us esa le; vf/kd yxrk gSaA (2) dqN ,slh Transaction ftUgsa Update dj fn;k x;k gSa os Hkh Log Records esa 'kkfey gksrh gSa ftlls Recovery

esa le; vf/kd yxrk gSaA bl izdkj ds mifjO;;ksa dks gVkus ds fy;s Check Points ds Concept dks rS;kj fd;k x;kA

(1) lHkh Log Records dks Stable Storage ls Main Memory esa ykuk (2) lHkh Updated Buffer Block dks ,d rjQ djukA (3) Stable Storage esa mijksDr Log Record ij Check Point ¼psdikWbUV½ yxkukA

BUFFER MANAGEMENT (1) Log-Record Buffering (2) Database Buffering

;fn System esa Data Transfer Faliure Occur gqvk gS] rks System blds fy;s Recovery Procedure ¼fjdojh izkslhtj½ pykrk gSaA ftlls Database dks iqu% Consistent State esa yk;k tkrk gSaA blds fy;s System Database ds gj Block ds fy;s nks Physical Block rS;kj djrk gSa] ftUgsa ,d gh LFkku ij j[kk tkrk gSaA tc Database ij Operation fd;k tkrk gSa] rks fuEu Steps dks Follow fd;k tkrk gSa%&

(1) lcls igys Information dks igys Block esa Store ;k Write fd;k tkrk gSaA (2) tc First Write Operation lQyrkiwoZd iw.kZ gks tkrk gSa] rc blh Information dh Copy Second Block esa

dj nh tkrh gSaA (3) bl izdkj Second Block ij Information Copy djus ds ckn gh Operation Complete gksrk gSaA

(1) Log Record Buffering:- ge tkurs gSa fd gj Log Record tc Create gksrk gSa] rks mls Stable Storage esa LVksj dj fn;k tkrk gSaA ijUrq cgqr ls mifjO;; Hkh bl Storage esa 'kkfey gksrs gSaa tSls%& Stable Storage dks Blocks esa ck¡Vk tkrk gSa o eq[;r% Log Records ds Size mu Blocks ls cgqr de gksrh gSa ftlls Memory Block dk dqN Hkkx [kkyh gh jg tkrk gSaA vr% blds fy;s vko’;d gSa fd ,d&,d Log Record dks Stable Storage esa u j[kdj ,d Block Size ds Log Records dks ,d lkFk bdV~Bk dj fQj mls Stable Storage eas Store fd;k tk,A vr% bu lHkh Log Records dks ,d lkFk bdV~Bk djus ds fy;s Main Memory esa Buffer Allocate dj nh tkrh gSaA

bl Buffer dks Log Buffer dgk tkrk gSaA vr% ,d lkFk lHkh Log Records dks Block Size ds vk/kkj ij Buffer esa ,df=r dj fy;k tkrk gSa rFkk ckn esa mls Stable Storage ds Block esa LVksj dj fn;k tkrk gSaA bu Log Records dks Stable Storage esa mlh Øe esa LVksj fd;k tkrk gSa ftl Øe esa ;s Records Log Buffer esa gksrs gSaA

Log Buffering ds dkj.k Log Records dks flQZ Main Memory esa dqN le; ds fy;s j[kk tkrk gSa rFkk ckn esa mUgsa Stable Storage esa Store djrs gSaA ijUrq ;fn Main Memory esa Log Records dks j[kk x;k gSa o System Crash gks tkrk gks bl fLFkfr ds fuEu Recovery Procedure ¼izkslhtj½ dks viuk;k tkrk gS%&

(i) dksbZ Hkh Transaction ¼Vªk¡tsD’ku½ ti rHkh Commit State esa tk,xh tc <Ti Commit> Log Record dks Stable Storage esa fy[k fn;k tk,A

(ii) <Ti Commit> Log Records dks Stable Storage esa j[kus ls igys ti ls lacaf/kr lHkh Log Records dks Stable Storage esa fy[k fn;k tkuk pkfg;sA



(iii) Data Operations ;k Log Records dks Database esa Write djus ls igys lHkh Log Records dk Stable Storage esa gksuk vko’;d gSaA

bl fu;e dks (WAL) Write Ahead Logging dgk tkrk gSaA Buffered Log dks Disk ij Write djuk Log Force dgykrk gSaA

Database Buffering:- System Database dks Nonvolatile Storage esa Store djrk gSa rFkk tc MkVkcsl esa Operation djus gks rks fdlh Specific Data Block dh dkWih dks Main Memory esa yk;k tkrk gSaA D;ksafd Database dh vis{kk Main Memory cgqr NksVh gksrh gSaA vr% ;g vko’;d gSa fd fdlh nwljs Block dks Memory esa ykus ls igys] igys Block dks iqu% Disk ij Write dj fn;k tk,A vr% Block b1 ij ;fn Operation Perform gks pqdk gSa rks igys b1 Block dks ckgj dj Block b2 dks Main Memory esa yk;k tk,xkA blds fy;s Virtual Memory Concept dks mi;ksx esa fy;k tkrk gSaA blds fy;s fuEu Steps esa Operation Perform fd;s tkrs gSa%&

(1) b1 ls laca/khr lHkh Log Records dks Stable Storage esa Store djukA (2) Block b1 dks Disk ij fy[kukA (3) Block B2 dks Main Memory eas ykukA

ijUrq ;fn Block b1 ds }kjk Block b2 dks Call fd;k tkrk gSa rks Hkh B1 ds lHkh Output dks Buffer Use esa ysdj Stable Storage esa j[k fn;k tkrk gSa rFkk ckn esa Block B2 dks main Memory esa yksM fd;k tkrk gSa] tc b2 dk dk;Z iw.kZ gks tkrk gSa rks mlds Output dks Stable Storage esa j[k b1 dks Execute fd;k tkrk gSa o var esa Blocks dks Disk ij fy[k fn;k tkrk gSaA

SHADOW PAGING (1) Recovery dh ,d vU; fof/k gSa ftls Shadow Paging dgk tkr gSaA (2) bl Technique esa Database dks Fixed length bbcks esa ck¡Vk tkrk gSa ftUgsa Pages dgrs gSaA (Pages

Operating System dk Concept gSa ftls Memory Management ds fy;s mi;ksx esa fy;k tkrk gSaA (3) ekuk fd Database dks 1 ton Pages esa ck¡Vk x;k gSa ijUrq ;s Page disk ij fdlh Order ¼Øe½ esa ugha gSaA (4) ;fn Database ds fdlh ist ij Operation djuk gks rks ml ist rd Page Table ds }kjk igq¡pk tkrk gSaA (5) Page Table esa N Entries gksrh gSaA gj Entry Database ds ,d Page dks iznf’kZr djrh gSaA (6) gj Entry ds lkFk Pointer Hkh gksrk gS] tks Disk ij Page dks Point djrk gSaA (7) igyh Entry Database ds igys ist dks iznf’kZr djrh gSa o Second Entry nwljs ist dks iznf’kZr djrh gSaA (8) Shadow Paging rduhd dk eq[; Idea ;g gSa fd blesa nks Page Tables dks Maintain fd;k tkrk gS%& (1)

Current Page Table (2) Shadow Page Table (9) tc dksbZ Transaction Perform dh tkrh gSa nksuks Page Tables esa Same Entries gksrh gSaA Shadow Page

Table Transaction ds nkSjku dHkh Change ugha gksrhA (10) ijUrq Current Page Table Transaction ds Write Operation ds nkSjku Change gksrh jgrh gSaA (11) lHkh Input rFkk Output Operation ds fy;s Current Page Table dks mi;ksx esa fy;k tkrk gSaA

ekuk fd Transaction Ti Write (x) Item Operation Perform djuk pkgrk gSa rFkk X Data Item fdlh ith Page ij iM+k gSaA System }kjk Write (x) Operation fuEu izdkj Perform fd;k tkrk gS%&

(1) ;fn ith Page ¼ftlesa X data Item Stored gSa½ Main Memory esa ugha gS] rks System }kjk lcls igys Input (x) Operation Perform fd;k tkrk gSaA

(2) ;fn Transaction }kjk bl ith Page ij igyk Write Operation Perform fd;k tk jgk gSa rks System Current Page Table dks fuEu izdkj ls Change djrk gSa%&

(i) lcls Disk ls ,d Unused Page dks fy;k tk,xkA ¼eq[;r% Database ds ikl free Pages dh List gksrh gSa½ (ii) bl Free Page dh Entry dks Database dh Free Page List esa ls gVkuk o ith Page ds Data dks u;s ist ij

dkWih djukA (iii) vc Current Page Table esa ml ith Page dh Entry ds fy;s u;s ist ds Pointer dks Allocate dj fn;k

tk,xkA ftl in ith Page dh dkWih dh xbZ FkhA vc X dh ubZ Value xj dks buffer esa j[k fn;k tkrk gSaA



Shadow Page Table dks Disk ij Store fd;k tkrk gSaAftlls transaction execution state dks Recovery dh tkrh gS A tc transaction Commit gks tkrh gSa rks System }kjk mls Current Page Table ls Disk ij Store dj fn;k tkrk gSaA vr% Current Page Table }kjk u;h shadow Page Table cuk nh tkrh gSA bl izdkj Current Page Table Main Memory esa LVksj jgrh gSa o Shadow Page Table Disk ijA ;fn Crash ds nkSjku Current Page Table Lost (destroy) gks tkrh gSa rks System }kjk Shadow Page Table ls Recovery dj yh tkrh gSaA vkSj mlh Shadow Page Table dh Copy iqu% Main Memory esa dj Current Page Table cuk nh tkrh gSaA

1

2

3

4

n

.

.

.

.

.

.

.

. Page Table

Simle Page Table Pages on disk

1

2

3

4

5

6

7

1

2

3

4

5

6

7

Shadow Page Table (Disk)

Page disk

Current Page Table (Main Memory)

Dbms Hindi

Documents

Transcript of Dbms Hindi