In a Relational Database Management System R DBMS, the data is logically organized in which basic structure?

Introduction / Context:
Relational Database Management Systems, often abbreviated as RDBMS, are based on the relational model proposed by Edgar F Codd. This model represents data in a specific logical structure that distinguishes RDBMS from hierarchical or network database models. Understanding this basic structure is fundamental to grasping how relational databases organise and access information.

Given Data / Assumptions:

• The question explicitly refers to R DBMS, meaning relational database systems.
• We must identify the core logical structure used to store data.
• Answer choices mention hierarchical trees, tables, linked lists, network graphs, and unstructured blobs.
• We are concerned with logical organisation rather than physical storage details.
• Standard relational database concepts apply.

Concept / Approach:
In the relational model, data is represented as relations, which are implemented as tables. Each table consists of rows and columns. Rows represent individual records or tuples, and columns represent attributes or fields. This tabular structure allows for powerful operations such as selection, projection, and joins. Other data models, such as hierarchical or network models, use trees or graphs, but those are not the basis of relational systems.

Step-by-Step Solution:
Step 1: Recall that RDBMS stands for Relational Database Management System and is based on relations. Step 2: Recognise that a relation in this context is typically represented as a table in practical implementations. Step 3: Understand that tables are composed of rows and columns, forming a tabular structure. Step 4: Compare this understanding with the options and identify the one that mentions a tabular structure of rows and columns. Step 5: Choose the option that most accurately matches the relational model.

Verification / Alternative check:
Any introductory database textbook states that relational databases store data in tables. Diagrams and examples consistently show tables with columns like CustomerId, Name, and Address, and rows representing individual customers. This reinforces that the core structure is tabular rather than hierarchical or network based.

Why Other Options Are Wrong:
Option A describes a hierarchical structure, which is used by older database systems and some directory services but not by relational databases. Option C describes a linked list, which is a low level data structure, not the logical organisation in an RDBMS. Option D references a network graph, which is closer to network or graph databases. Option E mentions unstructured blobs, which do not describe the overall logical structure of an RDBMS, even though blobs can be stored within tables.

Common Pitfalls:
A common misconception is confusing physical storage structures with logical organisation. While relational databases may internally use various data structures such as B trees, the user and logical view remains tabular. Another pitfall is to assume that any database that stores data in files or in a hierarchy is relational, which is not accurate.

Final Answer:
In an RDBMS, data is logically organised in a tabular structure of rows and columns known as tables..