Let us discuss the difference between hierarchical model and relational database model?
Hierarchical model
- Hierarchical model is tree like structure.
- In the structure where the parent is only one parent in all over structure organization of any object. The parent who has no parent in the structure is also known as grandparent.
- In the structure the child quantity is two or more than two in numbering.
- The base of the hierarchical model is inheritance of the hierarchical character which means the hierarchical character relates as inherit their properties in the form of one to many relation.
- The hierarchical structure shows the connection using connection line in the model.
Image reference of the hierarchical model of the basic components in their structure model
In the given model there are three layers of the hierarchical model
shows in the image. From the top to bottom direction first layer is the “grand
parent”, second is “parent family” and third one is “children family”. In the
model you can also add the layer at the top of the grand parent is the “great grandparent”
above the grandparent layer.
Now back to the main point the children family is minimum attribute of
every child entity. So you can say it is also called lowest class entities in
the whole model that works for the parent entities which is connected to the
parent family layer.
The parent family is more than higher level entity in the whole model
that work for grandparent layer or family. The parent family is the more
advance than the children family entities that smartly.
In the grandparent class level that makes a final decision of the whole database structure to operate the whole system according to the hierarchical model. You can say the grandparent is the root of the higher level of the database is called highest level database in the structure.
Relational model
- The relational model is a table like a structure.
- There is no parent in the model because in the relation there are group of records which has own unique identity of every records object data recorded in the tuples one by one.
- In the structure the attributes of a record can create in large number of quantity for every record.
- The base of the relational model is matrix structure which is called the combination attribute and a record. It is in the tabular form where the record is in the horizontal direction and the attribute is vertical direction. The cross connection of the attribute and record is a cell.
- The unique identity is a primary key or serial number of a record to identify.
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