When does case matter in Oracle SQL? Assess the claim: "Only inside string literals."

Introduction / Context:
Oracle SQL treats unquoted identifiers and keywords case-insensitively, but case sensitivity is still significant in several areas. The statement that it matters “only inside strings” is incomplete and therefore incorrect.

Given Data / Assumptions:

• String literals in single quotes preserve case and compare case-sensitively unless functions or case-insensitive collations are used.
• Quoted identifiers in double quotes preserve case and must be referenced exactly.
• Some NLS collation settings impact case sensitivity of comparisons.

Concept / Approach:
Unquoted identifiers are folded to uppercase and are case-insensitive. However, "MyTable" is distinct from MYTABLE and must be referenced precisely if created with quotes. Furthermore, case can influence string comparison outcomes depending on collation settings (for example, BINARY vs. case-insensitive collations). Hence, the claim that only strings care about case omits the quoted identifier scenario and collation effects.

Step-by-Step Solution:

Verification / Alternative check:
DESCRIBE "Emp" vs. DESCRIBE EMP shows the necessity of exact case when quotes were used. String comparison functions (e.g., UPPER) normalize case explicitly.

Why Other Options Are Wrong:

• Claiming “valid” ignores quoted identifiers and collation behavior.
• Optimizer mode or character set alone does not dictate identifier case rules.

Common Pitfalls:
Creating quoted identifiers unintentionally; mixing case in client code; assuming all databases behave the same regarding case.

Final Answer:
Invalid (case also matters for quoted identifiers and some collations)