-1" OR 3*2>5 --

That string is a classic SQL injection payload. Here’s the safe, exam-focused explanation without enabling misuse:

• The snippet -1" OR 3*2>5 -- is designed to break out of a query’s intended logic.
• In many SQL dialects:
  • "-1" is a string literal (or can be coerced to a numeric value -1).
  • 3*2>5 evaluates to true (since 6 > 5).
  • OR means true OR something is true.
  • The -- starts a comment, so the rest of the statement is ignored.
• So the overall effect is that the injected condition evaluates to true. If this were placed into a WHERE clause or login check, it could bypass the intended restrictions.

Important defensive notes (exam-safe, practical defenses):

• Use parameterized queries / prepared statements (never concatenate user input into SQL).
• Validate and sanitize input, and apply strict typing where possible.
• Use least-privilege database accounts (no read/write access where not needed).
• Disable multi-statement execution if your DBMS supports it.
• Consider using an ORM or stored procedures with proper binding.
• Employ input-length checks and escaping only as a last resort (not as the primary defense).

If you want, I can turn this into a short exam-style question set (e.g., “Why is this dangerous? How would you fix it? What would happen on a WHERE clause?”) or provide a few safe practice problems on SQL injection defense.