The difference between DBMS and DBMS

Question

This happened to me when I read about PostgreSQL on his wiki page, where he calls himself ORDBMS. I always knew about Microsoft SQL Server, which is an RDBM system. Can someone help me understand the main differences between a relational database management system (RDBMS) and an object relational database management system (ORDBMS) and in which scenarios should I use one of them?

In addition, my key question is related to the fact that in the Microsoft SQL Server world we often use the Entity Framework (EF) layer to perform relational object mapping on the application side. So, in the ORDBMS world, are all the ORM responsibilities already completely fulfilled by the database itself, or there may be cases or use cases in which I would end up using an ORM-like Entity Framework on top of ORDBMS? Do people even use ORM on top of ORDBMS?

Answer 1

Most players in the database do not support it or do not support it exclusively. It is complex and not widely used. Even if “data” is OO by nature, databases existed several decades ago and they cannot accept ORDBMS (or OODBMS). The learning curve also creates problems.

ORDBMS / OODBMS is like viewing the virtual registry that you see in the registry editor. Content is wood style objects. But internally they can be saved as flat / hierarchical or relational. You really don't care - the APIs provide you with registry information.

Similarly, even if major players do not support (and will not support) the nature of the OO database, they can provide some extensions. Or, you may have to create your own framework for OO data. A database of films with actors and directors can be represented using relationships (tables). Actors, directors, filming locations will also be classes / objects and can be easily represented using tables and referential integrity imposed by the database / database developer.

You, as a developer, would make this relational nature of the data an object-oriented form that has Movie as a class, referencing members / directors (1: 1 or 1: N). I do not know how / that EE facilitates this, but it will only do this method.

Object Relational Databases

• Object-oriented technology on top of relational technologies and in a relational context.
• Objects are stored in object tables, not row tables.
• Support for basic object-oriented functions: complex types, inheritance, aggregation, methods
• Benefit: Expanding Known Technology
• Disadvantages: A mixture of both technologies can lead to difficult to understand schemes.
• Has performance issues.
• Object-relational systems include features such as complexity of object extensibility, encapsulation, inheritance, and better interfaces for OO languages.
• ORDBMS allow developers to implement new classes of data objects in an abstraction of the relational data model (and over SQL).

The following diagram shows how to access data.

Answer 2

Taken from http://www.aspfree.com/c/a/database/introduction-to-rdbms-oodbms-and-ordbms/ :

RDBMS

The core elements of an RDBMS are based on the Ted Codds 13 rules for a relational system, the concept of relational integrity, and normalization. The three pillars of a relational database are that all information should be stored in a table, where all data is described using data values. Secondly, each value found in the columns of the table is not repeated. The last fundamental is the use of a standard query language (SQL).

The advantages of a DBMS are that the system is simple, flexible, and productive. Because tables are simple, data is easier to understand and communicate with others. RDBMSs are flexible because users do not need to use predefined keys to enter information. In addition, DBMSs are more productive because SQL is easier to learn. This allows users to spend more time typing, rather than learning. More importantly, the biggest advantage of an RDBMS is the ease with which users can create and access data and expand it if necessary. After creating the source database, new data categories can be added without modifying the existing application.

There are limitations to a relational database management system. First, relational databases do not have enough storage to process data such as images, digital and audio / video. The system was originally created to handle the integration of media, traditional field data, and templates. Another limitation of a relational database is its inadequacy of working with languages ​​outside of SQL. After its initial development, languages ​​such as C ++ and JavaScript were created. However, relational databases do not work effectively with these languages. A third limitation is the requirement that the information be in tables where relations between objects are determined by values.

ORDMS

Object Relational Database (ORDBMS) is the third type of database distributed today. ORDBMS are systems that "try to expand relational database systems with the functionality needed to support a wider class of applications, and in many ways provide a bridge between relational and object-oriented paradigms."

ORDBMS was created to handle new types of data, such as audio, video and image files, which relational databases were not equipped for processing. In addition, its development was the result of a wider use of object-oriented programming languages ​​and a large discrepancy between them and the DBMS software.

One of the advantages of ORDBMS is that it allows organizations to continue to use their existing systems without significant changes. The second advantage is that it allows users and programmers to use object-oriented systems in parallel.

There are problems when implementing ORDBMS. The first is storage and access methods. The second is query processing, and the third is query optimization.