State main categories of data models - Accountancy - Structuring Database for Accounting

Question

State main categories of data models

Saurabh Mehta · Accepted Answer

The following are the
various categories of data models
(i)  Relational
Data Model
(ii) Hierarchical
Data Model
(iii) Network Data
Model
1 Relational Data Model- This data model is
based on the relationship of collected data values In this data
model, data is organised into rows and columns A row is regarded as
a tuple, a column header is known as an attribute and the
collective set of rows and columns, i e a table is called a
relation The table is known as a relation as it expresses the
relationship between the rows and columns This model provides the
storage and retrieval functions and defines the data structure
The relational data
model was first introduced by Ted Codd in 1970 in a classic paper
Codd, 1970 Prior to this, there were other data models which were
proposed in sixties such as, hierarchical data model and network
data model These models are also known as legacy-models due to
their large existing user-base
2 Hierarchical Data Model- This data model
mainly consists of records and parent-child relationships While, a
record is regarded as a collection of values that provides
information regarding an entity or a relationship instance, on the
other hand, a parent-child relationship explains the relationship
between the parent record and children record type In this data
model, the records are organised in a tree structure rather than as
an arbitrary graph The data is represented by a collection of
records and relationship among data is represented by links
3 Network Data Model- This type of data model
is sometimes also known as DBTG model, as the original network
model was presented in CODASYL Data Base Task
Groupâ€™s 1971, i e (DBTG) This data model
basically consists of records and sets While, data is stored in
records, which consists of a group of related data values, on the
other hand, sets describes the relationship between two records
types In this data model, data is also represented by collection of
records and the relationship among data is represented by sets This
model provides many-to-many relationships in data

State main categories of data models.