What are the advantages and disadvantages of OODBMS?

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 Advantages of OODBMSS

OODBMSS can provide appropriate solutions for many types of advanced database applications. However, there are also disadvantages.

  • Enriched modeling capabilities:

The object-oriented data model allows the 'real world' to be modeled more closely. The object, which encapsulates both state and behavior, is a more natural and realistic representation of real-world objects. An object can store all the relationships it has with other objects, including many-to-many relationships, and objects can be formed into complex objects that the traditional data models cannot cope with easily.

  • Extensibility: 

OODBMSs allow new data types to be built from existing types. The ability to factor out common properties of several classes and form them into a super-class that can be shared with sub-classes can greatly reduce redundancy within the system and is regarded as one of the main advantages of object orientation. Further, the reusability of classes promotes faster at development and easier maintenance of the database and its applications.

  • Capable of handling a large variety of data types:

 Unlike traditional databases (such as hierarchical, network, or relational), the object-oriented database is capable of Pastoring different types of data, for example, pictures, voice video, text, numbers, and so on.

  • Removal of impedance mismatch: 

A single language interface between the Data Manipulation Language (DML) and the programming language overcomes the impedance mismatch. This eliminates many of the efficiencies that occur in mapping a declarative language such as SQL to an imperative 'language such as 'C'. Most OODBMSs provide a DML that is computationally complete compared with SQL, the 'standard language of RDBMSs.

  • More expressive query language: 

Navigational access from the object is the most common form of data access in an OODBMS. This is in contrast to the associative access of SQL (that is, declarative statements with selection based on one or more predicates). Navigational access is more suitable for handling parts explosion, recursive queries, and so on.

  • Support for schema evolution: 

The tight coupling between data and applications in an OODBMS makes schema evolution more feasible.

  • Support for long-duration, transactions: 

Current relational DBMSs enforce serializability on concurrent transactions to maintain database consistency. DBMSs use a different protocol to handle the types of long-duration transactions that are common in many advanced database applications.

  • Applicability to advanced database applications: 

There are many areas where traditional DBMSs have not been particularly successful, such as Computer-Aided Design (CAD), Computer-Aided Software Engineering (CASE), Office Information systems (OIS), and Multimedia Systems. The enriched modeling capabilities of OODBMSs have made them suitable for these applications.

  • Improved performance: 

There have been a number of benchmarks that have suggested OODBMSs provide significant performance improvements over relational DBMSs. The results showed an average 30-fold performance improvement for the OODBMS over the RDBMS.


Disadvantages of OODBMSs

There are the following disadvantages of OODBMSS:

  • Lack of universal data model: 

There is no universally agreed data model for an OODBMS, and most models lack a theoretical foundation. This .disadvantage is seen as a significant drawback and is comparable to per-relational systems.

  • Lack of experience: 

In comparison to RDBMSs, the use of OODBMS is still relatively limited. This means that we do not yet have the level of experience that we have with traditional systems. OODBMSs are still very much geared towards the programmer, rather than the naïve end-user. Also, there is a resistance to the acceptance of the technology. While the OODBMS is limited to a small niche market, this problem will continue to exist

  • Lack of standards: 

There is a general lack of standards for OODBMSs. We have already mentioned that there is not universally agreed data model. Similarly, there is no standard object-oriented query language.

  • Competition:

Perhaps one of the most significant issues that face OODBMS vendors is the competition posed by the RDBMS and the emerging ORDBMS products. These products have an established user base with significant experience available. SQL is an approved standard and the relational data model has a solid theoretical formation and relational products have many supporting tools to help both end-users and developers.



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