Relation base model
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The document summarizes the relational database model, its benefits, and limitations. The relational database model represents data using tables of columns and rows, and was invented by Edgar Codd in 1969. Key benefits include ease of use, flexibility in linking data, precision through relational algebra, security controls on tables, and the use of SQL for data manipulation. Limitations are potential performance issues with large tables, physical storage consumption, and slower extraction of hierarchical data meanings compared to other models.
Relation base model
- 1. Relational Database Model It’s benefits & limitations By Jatin Chhabra
- 2. Relational Database Model • Relational Database Model is a based on tables and for management purposes. This model was invented by Edgar F. Codd in 1969. Edgar at that time was working at IBM. In the relational model of a database, all data is represented in terms of “tuples” & grouped into “relations”. A database organized in terms of the relational model is a relational database.
- 3. Table 1.1 S.no Hotel City State Rooms Front desk Restaurant Travel Desk Parking Room rate 1 ABC A AA 12 Yes Yes Yes No 1000 2 XYZ S DD 23 Yes Yes Yes Yes 2000 3 AAA D SS 34 Yes Yes Yes Yes 1200 4 CCC F FF 43 Yes Yes Yes Yes 2300 5 BBB G GG 12 Yes No Yes Yes 3000 6 DDD H HH 32 Yes No No Yes 1000 7 FFF J JJ 45 No No No Yes 700 • From S.no to Room rates is Attributes • From 1 to 7 is Tuple
- 4. Benefits of Relation base model Relational Database Model is widely used around the world, as its: 1. Easy to use: In Relational model data is easily presented & visible. So revision becomes quite easy as the information is stored in simple tables & rows. Such data id find attractive for the first time user. 2. Flexibility: An operator or a user can easily link & extract the data & can easily get the desired information easily. 3. Precision: The usage of relational algebra and calculus in the manipulation of the relations between the tables ensures that there is
- 5. no ambiguity (doubtfulness or uncertainty), which may otherwise come while establishing the links in a complicated network type database. 4. Security: Security control & authorization can be implemented on various tables, which gives a sense of control to the creator of the table. If someone requires the protective data then she/he needs to have the permission from the creator. 5. Data Independence: Data independence is achieved easily with normalization structure, used in a relational database than in the more complicated tree or network structure.
- 6. 6. Data Manipulation Language: The possibility of responding to query by means of a language based on relational algebra and relational calculus e.g SQL is easy in the relational database approach. For data organized in other structure the query language either becomes complex or extremely limited in its capabilities.
- 7. Limitations of relational database model 1. Performance: A major constraint in the use of relational database system is machine performance. If there is an enormous data in the tables then the performance gets affected in responding to the sql queries. 2. Physical Storage Consumption: With an interactive system, for example an operation like join would depend upon the physical storage also. It is, therefore common in relational databases to tune the databases and in such a case the physical data layout would be chosen so as to give good performance in the most frequently run
- 8. operations. It therefore would naturally result in the fact that the lays frequently run operations would tend to become even more shared. 3. Slow extraction of meaning from data: If the data is naturally organized in a hierarchical manner and stored as such, the hierarchical approach may give quick meaning for that data.
- 9. Note : The current slide is free sample created by Jatin Chhabra. Selling the same will be viewed as a offence.
- 10. Note : The current slide is free sample created by Jatin Chhabra. Selling the same will be viewed as a offence.