ADBMS 19MCA8125.pdf
- 1. Name - Shubham Pathania Class - MCA (LEET) UID - 19MCA8125 Subject - ADBMS (CAT-762) Group - 4th Submitted to Submitted by Sandeep Kaur Shubham Pathania
- 2. INDEX Sr No. Contents Page no. 1 Compare and Contrast multi database system with centralized system 1-2 2 Explain various factors that affect the selection of DBMS software. 2-3 3 Check if a given a year is a leap year. The condition is:- Year should be (divisible by 4 and not divisible by 100) or (divisible by 4 and divisible by 400.) Display the output on the screen using dbms_output.put_line. The year should be input by the user. 4 4 Ask the user to enter the weight of an apple box. If the weight is >= 10 kg, rate =Rs. 5/kg weight is < 10 kg, rate = Rs. 7/kg Calculate the cost of the apple box. Display the output on the screen using dbms_output.put_line 5 5 Program should accept the age of the user. Depending upon the following conditions it should output:- age <18 years? Child? Age >= 18 years and <21 years? Major? Age >= 21years? Adult? 6
- 3. 1. Compare and Contrast multi database system with centralized system? Ans There are many aspect that let us make a comparison between centralized and distributed DBMS: Database management system is any software that manages and controls the storage, the organization, security, retrieval and integral of data in a specific database, whereas DDBMS consist of a single database that is divided into many fragments. Each fragment is integrated on one or more computer and controlled by independent database (DBMS). In centralized DBMS the data is distributed across the network computers, and the data is stored on many sites and under the management responsibility of DDBMS. But in the DBMS data is stored and controlled in a central site. Both of DDBMS and centralized DBMS provide the access to database using the same interface, but for this function centralized DBMS faces less complication than DDBMS. For distributing data over network we can use replication or fragmentation. The objective of replication and fragmentation is to make a transparency of this allocation to make the details of implementation hidden on users. In centralized DBMS is not need to make transparencies. In DDBMS design we can find three issues which are not in centralized DBMS design. Consequently, centralized DBMS is less sophisticated than DDBMS because it not supports the organizational structure of today’s widely distributed enterprises, and DDBMS more reactive and reliable. Difference - Centralized DBMS Distributed DBMS Data is stored only on one site Data is stored on different sites Data stored in single computer can be used by multiple users Data is stored over different sites which are connected with each other. If centralized system fails, then the entire system is halted. If one of the system fails, then user can access the data from other sites.
- 4. Centralized DBMS Distributed DBMS Centralized DBMS is less reliable and reactive Distributed DBMS is more reliable and reactive Centralized DBMS is less sophisticated Distributed DBMS is more sophisticated Presence of a global clock Lack of a global clock One single central unit Concurrency of components 2. Explain various factors that affect the selection of DBMS software. Ans Data Model For a long time, the relational concept was dominant, however recently NoSQL databases have again become more successful. Relational vs. NoSQL is based on your individual needs and their main advantage is the data structure itself. To decide on which model works best for you, you should ask yourself: Do you have a data structure which you can easily reflect in a relational model or do you need to work with unstructured data? How do you retrieve and work with the data? For example, analysis of hierarchical data in sequential files is faster in a NoSQL database then in a relational one. Since relational databases have a long history, you find a lot of commercial RDBMS (relational DBMS), whereas NoSQL databases are often available as open source. 2. Data Consistency Nowadays, collecting data is not a big effort any more. But, keeping the data consistent becomes even more important as more sources feed into the database. Therefore, consistency rules are very important and the ability to define these should be considered when choosing a new DBMS. 3. Data Security For most companies, data availability is a key business success factor and should be guaranteed at all times. The ability to backup and restore the databases is essential and needs to be possible with your chosen DBMS. IT Administrators should setup a framework and a management plan for data security and ensure as little downtime as possible. 4. Data Protection Access protection and encryption should allow protection of personal data. Every DBMS provide different methods of protect the data through encryption, but the possibility to define routines and access rights is different for every system. The method of data protection depends on the
- 5. structure of data and should be carefully considered during the evaluation process of a DBMS. 5. Multi Access and Integration Setting up a DBMS, running it and extending it for future growth, requires enough flexibility to allow integration into the given IT infrastructure. Furthermore, the DBMS needs to allow concurrent accesses by multiple users. Synchronization and integration with other tools are essential for smooth workflows. 6. Efficiency When we talk about the efficiency of DBMS, we usually mean the response time. You will find on premise and cloud solutions available on the market. Depending on your own IT infrastructure, a cloud based solution can have certain disadvantages, as you rely on network services and latencies of network providers. On the other side, cloud computing can provide more and better resources compared to your on premise infrastructure, as efficiency is also related to scalability. Make sure your DBMS of choice can scale to your needs. 7. Usability Different user groups will be working with the DBMS. There are the administrators, IT and Database admins, application integrators and data consumers. All these different roles need an easily understandable query language and intuitive UI to use the DBMS system efficiently. The easier it is for the user to work with the DBMS, the lower the cost will be for people. 8. Implementation and Service Costs The modifiability and availability of support and documentation needs to be taken into consideration as part of the implementation and Total Cost of Ownership (TCO). Development needs must always be included, as Database Management Systems need to be shaped to the individual company’s need. A clear overview of these needs and costs will help to choose the right tool. Vendor or community support as well as comprehensive documentation will save you time and money. 3. Check if a given a year is a leap year. The condition is:- Year should be (divisible by 4 and not divisible by 100) or (divisible by 4 and divisible by 400.) Display the output on the screen using dbms_output.put_line. The year should be input by the user. Ans DECLARE year NUMBER: = 1600; BEGIN IF MOD (year, 4) =0
- 6. AND MOD (year, 100)!=0 OR MOD (year, 400) =0 THEN dbms_output.Put_line(year || ' is a leap year '); ELSE dbms_output.Put_line(year || ' is not a leap year.'); END IF; END; 4. Ask the user to enter the weight of an apple box. If the weight is >= 10 kg, rate =Rs. 5/kg weight is < 10 kg, rate = Rs. 7/kg Calculate the cost of the apple box. Display the output on the screen using dbms_output.put_line Ans DECLARE weight number:=&apple_weight; rate number; BEGIN IF (weight>=10) THEN rate:=5; ELSE rate:=7; END IF; dbms_output.put_line('TOTAL WEIGHT'||weight||'TOTAL COST '||(weight*rate)); END; /
- 7. 5. Program should accept the age of the user. Depending upon the following conditions it should output:- age <18 years? Child? Age >= 18 years and <21 years? Major? Age >= 21years? Adult? Display the output on the screen using dbms_output.put_line Ans DECLARE age number:=&user_age; USER varchar(20); BEGIN IF (age<18) THEN USER:='child'; elsif (age>18) AND (age<21) THEN USER:='major'; ELSE USER:='adult'; END IF; dbms_output.put_line('user is '||USER); END; /