Database Management

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Data and Information Data is a collection of raw facts. Data of a student includes name, age, roll no,

class, sections etc. Data about a company includes area, employee

strength, revenue, clients etc. When ever data is being processed and meaning

is derived out of it , it is called information.

DATA INFORMATION

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File System File system has often has data tightly

coupled with the code, makes difficult to fix defects.

File System based applications generally occupies more space. For Eg: for file system it requires 500GB on the main memory to hold the data which is expensive.

Cannot access more data at a time with file system. For eg: for a 32 bit addressing system, the maximum data which could be addressed in limited

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File System ….contd Provides only password mechanism

for the file but not the data in the file else would need expensive encryption algorithms to be developed

Need to write special programs to address each user’s query and is complex.

Examples are: Winamp, Calculator, Real player all use file system.

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Database Introduction An Organized Collection of Information with a

common Purpose. A Collection of Data describing the Business

activities of one or more related organizations. Technically database means it’s a collection of

integrated set of interrelated information which are stored in an online medium with out redundancy.

Data Redundancy means the unusual repetition of information.

For Example: Employee payroll database Railway reservation database Library management database, etc.

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RDBMS: Relational Data base management System

RDBMS is defined as a collection of interrelated data stored together to serve multiple applications. RDBMS is robust and addresses the following disadvantages of earlier data management issues like : Data redundancy and inconsistency Difficulty in accessing data Data Isolation Concurrent access anomaly Security problems Efficiency and scalability issues

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DBMS and DB ApplicationDatabase

ManagementSystem

DB schema, eg., Emp(ssn, name, addr, sal)

Dept(id, dept-name)

DB application, eg.,/* C program with embedded SQL*/

DB

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Skill Requirements for Database Testing

SQL Queries, Joins RDBMS concepts Understand ER diagram Understand Table structures and Data

types Mapping Data type in front and back end

and compatibility checking Data migration

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Automated Database Testing

Tools shows the differences coded once and verified repeatedly ; and can report the defect to the developer quickly.

Tools used are: Win runner QTP RFT Silk Test Perl Python