In a proper relation, does the order of the columns (attributes) matter for the meaning of the data?

Introduction / Context:
Attributes in a relation form a set, and sets have no inherent order. This question checks whether column order is semantically meaningful in the relational model.

Given Data / Assumptions:

• A relation is defined over a set of attributes, not an ordered list.
• SQL may display columns in a chosen order, but that is presentation.
• Users can request any explicit order in SELECT lists.

Concept / Approach:
Because attributes are a set, shuffling column positions does not change the relation’s meaning. Only attribute names and their domains matter. Any dependence on visual position is a UI concern, not a relational one.

Step-by-Step Solution:

Verification / Alternative check:
Write SELECT y, x FROM T; it is the same data as SELECT x, y FROM T reordered; the schema is unchanged.

Why Other Options Are Wrong:

• “Incorrect” conflicts with fundamental set semantics.
• Mentions of SELECT * or composite keys are implementation/presentation issues, not changes to meaning.

Common Pitfalls:
Believing that position in CREATE TABLE determines semantics. It determines default display order only.

Final Answer:
Correct