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Relational Database Management Systems emerged in the 1980’s, and have dominated the database industry since. ... Object Database Management Systems have been developed to correct this mismatch. ... With ORDBMS they would have the best of both worlds: RDBMS functionality with the advantages of an already coded OO-to-data interface; no migration issues and fewer upgrade concerns than moving to a completely new database approach. ... Database Implementation Approaches
Early on, programmes used application specific data architectures, often referred to as Flat File databases, with data stored as a table of information separated by delimiters such as commas or colons [CTDP01], and generally in a format only its specific programme could read and write [WALK03]. ...
With the growth of large quantities of data, dedicated Database Servers emerged with a Server Programme that communicated with remote clients and managed the files containing that data [CTDP01]. ... In the 1970’s databases using Hierarchal and Network Data Models [WALK03] [COMM90] emerged, classified as FIRST GENERATION database systems. They were the first such systems offering substantial database management functions with Data Definition Language (DDL) and Data Manipulation Language (DML) support for collections of records [COMM90]. ...
To correct this, the Relational Model for data access was born [WALK03]; these SECOND GENERATION database systems emerged in the 1980’s and largely replaced the earlier First Generation systems [COMM90]. ... Today, Relational Database Management Systems (RDBMS) are the most common data storage model used [CTDP01] [LEAV]. ... Secondly, vendors realised the need for a more suitable database paradigm that overcame these issues and incorporated increasingly popular extended data types (video, audio, etc); and the THIRD GENERATION of DBMS’s - Object Database Management Systems (ODBMS) resulted [WALK03] [COMM90]. Object databases store objects in object form with class, state and behaviour information [CTDP01] rather than data in tables; effectively both applications and database could now use exactly the same object model [LEAV] [OBJE01]. ... These drawbacks meant all but the most niche OO customers stayed with RDBMS, and gave relational vendors the time to develop their own solution to the growth of complex data and OO - a hybrid “object-relational” solution - Object Relational Database Management Systems (ORDBMS) [FRES02]. ...
We will therefore recommend a suitable database approach for Southern Star from amongst the RDBMS, ODBMS and ORDBMS approaches, with consideration for the seemingly universal use of the OO paradigm in modern programming languages. ... Relation Database Management Systems (RDBMS)
Relational databases consist of several tables of simple data such as numbers, string values or dates; tables are two-dimensional and composed of rows (records) and columns (fields) [CTDP01]. ... Tables are ‘normalised’ using a set of design rules so data isn’t unnecessarily duplicated in the database [CTDP01]. ... Programmers must develop mapping procedures between their object model and the relational model of the database; sometimes spending more than 25% of their coding time just on mapping procedures [WALK03] [LEAV]. ... Object Database Management systems (ODBMS)
OO focuses on Classes of Objects, used to define the data and methods a model requires; Classes are therefore like an object template [CTDP01]. ... They support the modelling and creation of data as objects; such that OO programming and the OO database now use exactly the same object model [LEAV] [OBJE01]. This eliminates “Impedance Mismatch” and the “Relational Wall” caused when an OO application tries to use an RDBMS as its database [WALK03] [LEAV] [WADE98]; translating directly into lower programming costs and quicker application development, as no translation procedures are required to map objects to data. ... One report has shown that ODBMS performed comparably to a leading RDBMS on simple data structures and operations, but increasingly outperformed that RDBMS as data and relationship complexity increased [WADE98].
ODBMS works well for: CASE, CAD, and CAM (Computer Aided Software Engineering, Design and Manufacturing); Multimedia Applications (for instance a Hospital database might contain patient records, x-ray pictures, and 3D imaging scans); Commercial and Financial analysis [CTDP01] [LEAV].
ODBMS’s provide most of the staple database management infrastructure, tools and performance of their relational cousins [CTDP01] [FRES02] [WADE98], but none provide the full-functionality of current RDBMS’s [MULL96]. ... Object Relational Database Management Systems (ORDBMS)
Object relational databases are essentially relational databases extended with additional object oriented capabilities [CTDP01].
Approximate Word count = 3391
Approximate Pages = 13.6
(250 words per page double spaced)
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