Which column property would you use to require that a monetary amount in one column be less than another monetary amount in the same row (for example, discount_amount < total_amount)?

Introduction / Context:
Relational databases can enforce business rules at the schema level. A common rule compares values across columns within the same row (for example, a discount cannot exceed the total).

Given Data / Assumptions:

• The comparison is row-scoped (same row).
• We need a declarative way to enforce an inequality between two columns.

Concept / Approach:
Data constraints, typically a CHECK constraint, let you express rules such as discount_amount < total_amount. Data type defines format, null status controls presence, and default value provides a fallback value—none of those compare two columns.

Step-by-Step Solution:

Verification / Alternative check:
DBMS DDL shows CHECK constraints evaluating boolean expressions per row during INSERT/UPDATE.

Why Other Options Are Wrong:
Null status/Data type/Default value: None can enforce cross-column comparison by themselves.

Common Pitfalls:
Forgetting to consider NULL semantics (for example, when either column is NULL, the CHECK may evaluate to unknown and pass/fail depending on DBMS). Require NOT NULL if appropriate.

Final Answer:
Data constraints