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
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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
Database Management Systems
Developed By SMS (The best friends group) 2 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
Bachelor of Computer Application (BCA) Examination, December 2005 2BCA3 - DATA BASE MANAGEMENT SYSTEM
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 Management Systems
Developed By SMS (The best friends group) 3 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
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
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
Database Management Systems
Developed By SMS (The best friends group) 5 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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
Database Management Systems
Developed By SMS (The best friends group) 6 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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
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%&
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
Database Management Systems
Developed By SMS (The best friends group) 7 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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
(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
Database Management Systems
Developed By SMS (The best friends group) 8 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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
(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
Database Management Systems
Developed By SMS (The best friends group) 10 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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)
Database Management Systems
Developed By SMS (The best friends group) 14 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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
(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
∏ 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
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(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
(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
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
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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
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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%&
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
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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%&
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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
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
(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
(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
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
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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
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
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(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
(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
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
Database Management Systems
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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
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
Database Management Systems
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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
Database Management Systems
Developed By SMS (The best friends group) 27 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
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%&
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
Database Management Systems
Developed By SMS (The best friends group) 28 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
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
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
Database Management Systems
Developed By SMS (The best friends group) 29 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
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
Developed By SMS (The best friends group) 30 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
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
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%&
(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
;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
Database Management Systems
Developed By SMS (The best friends group) 31 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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
(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
;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
Database Management Systems
Developed By SMS (The best friends group) 32 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
(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
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
Database Management Systems
Developed By SMS (The best friends group) 33 Keen College Bikener (College of IT & Management) Ph. 9785306009,9983850627,9269069945
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