EVOLUTION IN DBMS

INTRODUCTION

DBMS is the system which stores the data in structural manner, and with standard format. Due to this system we can find, update, insert or can access any kind of data easily.

In past, there was a file system by which processes like insertion, updating, deletion of information are get difficult. file system is limited for small scale data and it get more difficult to handle large data.

So, to reduce this kind of deficiencies we invented different kind of data models to store the data in structural manner. in data models also, we found some disadvantages. so by again working on it, data models also get evolved.

Let see what is data model and evolution in data models.....

DATA MODEL

• Data model represents a conceptual representation of the data. it is a blueprint or structural format for database design.
• Data model insures data integrity and scalability.
• Data model insures data integrity and scalability. It defines how data is stored ,deleted, and can accessed.
• It is a way of storing data on a computer so that it can be used in a more efficient manner for further purposes.
• It is an abstract model that represents the data objects, data flow between these data objects, and the interrelationship between these data objects.

Let see the types of data model and how data model are evolved.....

TYPES OF DATA MODEL

1. HIERARCHICAL DATA MODEL :-

• Hierarchical data model is a tree like structure data model with parent-child relationship.
• hierarchical data model supports one to one and one to many relationships.

Disadvantages of hierarchical data model :-

• We have to go from top to bottom, to access any kind of data.
• Hierarchical data model does not supports many to one and many to many relationships.

Due to this kind of disadvantages, we created network data model over hierarchical data model.

2. NETWORK DATA MODEL :-

• Network data model organizes data in graph structure, in which one child can have multiple parents.
• Network data model supports all four relationships such as one to one, one to may, many to one and many to many.
• In network data model, there are multiple paths to access the particular data. so it becomes easy to find particular data.

Disadvantages of network data model :-

• It creates a complex structure, for large scale database.
• It is difficult to retrieve, insert and to delete the data.
• It has limited scalability and lack of standardization.

Due to this kind of disadvantages, we created relational data model over network data model.

3. RELATIONAL DATA MODEL :-

• The relational data model enforces the data consistency through the primary keys, foreign keys and integrity constraints.
• It has standard query language (SQL) and format, which makes easy to transfer the data between the system.
• The model allows for efficient data retrieval using SQL queries.

Disadvantages of relational data model :-

• Complex queries are difficult to optimize by using relational data model.
• The relational data model can lead to data redundancy and performance issues, if not properly designed.
• The model requires good understanding of SQL and database design principles.

Due to this kind of disadvantages, we created our final and latest data model as entity relationship data model over relational data model.

4. ENTITY RELATIONSHIP DATA MODEL :-

• Entity relationship data model is also known as ER model. it is a latest and common data model which is used nowadays to store data.
• ER model has components - entity, attribute and relationship.
• ER model describes interrelated things of interest in a specific domain of knowledge.
• It is a graphical representation that depicts relationships among people, objects, places, concepts or events in an information technology (IT) system.

CONCLUSION

DATA MODEL HELPS US TO STORE THE DATA IN STRUCURAL MANNER, AND MAKES THE PROCESSES LIKE INSERTION, SELECTION, DELETION AND UPDATION EASY. DATA MODELS ARE EVOLVED BY CONSIDERING THE DEFICIENCIES AND BY IMPROVING THE PERFOMANCES.

HERE IS THE LIST OF DATA MODELS, FROM PAST TO LATEST DATA MODELS :-

1. HIERARCHICAL DATA MODEL .
2. NETWORK DATA MODEL.
3. RELATIONAL DATA MODEL.
4. ENTITY RELATIONSHIP DATA MODEL.HIERARCHICAL DATA MODEL .

~Ved Malkunaik