There are four main types of database
management systems (DBMS) and these are
based upon their management of database
structures. In other words, the types of DBMS
are entirely dependent upon how the database
is structured by that particular DBMS.
Hierarchical DBMS:-
A DBMS is said to be hierarchical if the
relationships among data in the database are
established in such a way that one data item is
present as the subordinate of another one or a
sub unit. Here subordinate means that items
have "parent-child" relationships among them.
Direct relationships exist between any two
records that are stored consecutively. The data
structure "tree" is followed by the DBMS to
structure the database. No backward movement
is possible/allowed in the hierarchical database.
The hierarchical data model was developed by
IBM in 1968 and introduced in information
management systems. This model is like a
structure of a tree with the records forming the
nodes and fields forming the branches of the
tree. In the hierarchical model, records are
linked in the form of an organization chart. A
tree structure may establish one-to-many
relationship.....
Network DBMS:-
A DBMS is said to be a Network DBMS if the
relationships among data in the database are of
type many-to-many . The relationships among
many-to-many appears in the form of a
network. Thus the structure of a network
database is extremely complicated because of
these many-to-many relationships in which one
record can be used as a key of the entire
database. A network database is structured in
the form of a graph that is also a data
structure. Though the structure of such a DBMS
is highly complicated however it has two basic
elements i.e. records and sets to designate
many-to-many relationships. Mainly high-level
languages such as Pascal , C++ , COBOL and
FORTRAN etc. were used to implement the
records and set structures.
Relational DBMS:-
A DBMS is said to be a Relational DBMS or
RDBMS if the database relationships are treated
in the form of a table. There are three keys on
relational DBMS: relation, domain and
attributes. A network means it contains a
fundamental constructs sets or records.sets
contains one to many relationship,records
contains fields statical table that is composed of
rows and columns is used to organize the
database and its structure and is actually a two
dimension array in the computer memory. A
number of RDBMSs are available, some popular
examples are Oracle, Sybase , Ingress, Informix ,
Microsoft SQL Server, and Microsoft Access .
Object-oriented DBMS:-
Able to handle many new data types, including
graphics, photographs, audio, and video, object-
oriented databases represent a significant
advance over their other database cousins.
Hierarchical and network databases are all
designed to handle structured data; that is, data
that fits nicely into fields, rows, and columns.
They are useful for handling small snippets of
information such as names, addresses, zip
codes, product numbers, and any kind of
statistic or number you can think of. On the
other hand, an object-oriented database can be
used to store data from a variety of media
sources, such as photographs and text, and
produce work, as output, in a multimedia
format. [1]
Object-oriented databases use small,
reusable chunks of software called objects. The
objects themselves are stored in the object-
oriented database. Each object consists of two
elements: 1) a piece of data (e.g., sound, video,
text, or graphics), and 2) the instructions, or
software programs called methods, for what to
do with the data. Part two of this definition
requires a little more explanation. The
instructions contained within the object are
used to do something with the data in the
object. For example, test scores would be
within the object as would the instructions for
calculating average test score.
Object-oriented databases have two
disadvantages. First, they are more costly to
develop. Second, most organizations are
reluctant to abandon or convert from those
databases that they have already invested
money in developing and implementing.
However, the benefits to object-oriented
databases are compelling. The ability to mix and
match reusable objects provides incredible
multimedia capability. Healthcare organizations,
for example, can store, track, and recall CAT
scans, X-rays, electrocardiograms and many
other forms of crucial data.
management systems (DBMS) and these are
based upon their management of database
structures. In other words, the types of DBMS
are entirely dependent upon how the database
is structured by that particular DBMS.
Hierarchical DBMS:-
A DBMS is said to be hierarchical if the
relationships among data in the database are
established in such a way that one data item is
present as the subordinate of another one or a
sub unit. Here subordinate means that items
have "parent-child" relationships among them.
Direct relationships exist between any two
records that are stored consecutively. The data
structure "tree" is followed by the DBMS to
structure the database. No backward movement
is possible/allowed in the hierarchical database.
The hierarchical data model was developed by
IBM in 1968 and introduced in information
management systems. This model is like a
structure of a tree with the records forming the
nodes and fields forming the branches of the
tree. In the hierarchical model, records are
linked in the form of an organization chart. A
tree structure may establish one-to-many
relationship.....
Network DBMS:-
A DBMS is said to be a Network DBMS if the
relationships among data in the database are of
type many-to-many . The relationships among
many-to-many appears in the form of a
network. Thus the structure of a network
database is extremely complicated because of
these many-to-many relationships in which one
record can be used as a key of the entire
database. A network database is structured in
the form of a graph that is also a data
structure. Though the structure of such a DBMS
is highly complicated however it has two basic
elements i.e. records and sets to designate
many-to-many relationships. Mainly high-level
languages such as Pascal , C++ , COBOL and
FORTRAN etc. were used to implement the
records and set structures.
Relational DBMS:-
A DBMS is said to be a Relational DBMS or
RDBMS if the database relationships are treated
in the form of a table. There are three keys on
relational DBMS: relation, domain and
attributes. A network means it contains a
fundamental constructs sets or records.sets
contains one to many relationship,records
contains fields statical table that is composed of
rows and columns is used to organize the
database and its structure and is actually a two
dimension array in the computer memory. A
number of RDBMSs are available, some popular
examples are Oracle, Sybase , Ingress, Informix ,
Microsoft SQL Server, and Microsoft Access .
Object-oriented DBMS:-
Able to handle many new data types, including
graphics, photographs, audio, and video, object-
oriented databases represent a significant
advance over their other database cousins.
Hierarchical and network databases are all
designed to handle structured data; that is, data
that fits nicely into fields, rows, and columns.
They are useful for handling small snippets of
information such as names, addresses, zip
codes, product numbers, and any kind of
statistic or number you can think of. On the
other hand, an object-oriented database can be
used to store data from a variety of media
sources, such as photographs and text, and
produce work, as output, in a multimedia
format. [1]
Object-oriented databases use small,
reusable chunks of software called objects. The
objects themselves are stored in the object-
oriented database. Each object consists of two
elements: 1) a piece of data (e.g., sound, video,
text, or graphics), and 2) the instructions, or
software programs called methods, for what to
do with the data. Part two of this definition
requires a little more explanation. The
instructions contained within the object are
used to do something with the data in the
object. For example, test scores would be
within the object as would the instructions for
calculating average test score.
Object-oriented databases have two
disadvantages. First, they are more costly to
develop. Second, most organizations are
reluctant to abandon or convert from those
databases that they have already invested
money in developing and implementing.
However, the benefits to object-oriented
databases are compelling. The ability to mix and
match reusable objects provides incredible
multimedia capability. Healthcare organizations,
for example, can store, track, and recall CAT
scans, X-rays, electrocardiograms and many
other forms of crucial data.
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