In SQL data manipulation, which command is used specifically to change existing data values within rows of a table (rather than adding new rows)?

Introduction / Context:
SQL provides distinct commands for creating, reading, updating, and deleting data. Choosing the correct statement avoids unintended data changes. This question focuses on modifying existing values in existing rows.

Given Data / Assumptions:

• We need to change values already stored in a table.
• We are not inserting new rows or browsing.
• We want the canonical SQL verb for this operation.

Concept / Approach:
The UPDATE statement changes column values in one or more rows that match a WHERE clause. INSERT adds new rows; APPEND is non-standard SQL terminology (sometimes used in specific tools to mean insert); BROWSE is a UI action, not an SQL command. Therefore, the precise SQL command to change existing data is UPDATE.

Step-by-Step Solution:
Identify operation type: modify existing row values.Select UPDATE … SET column = value WHERE condition.Avoid commands that add rows (INSERT/APPEND) or just view data (BROWSE).

Verification / Alternative check:
SQL documentation and examples consistently show UPDATE as the verb to change values; transactions ensure atomicity and rollback on error.

Why Other Options Are Wrong:

• INSERT / APPEND: Add new rows rather than modify existing ones.
• BROWSE: Not a standard SQL DML command.
• None of the above: Incorrect because UPDATE is correct.

Common Pitfalls:
Forgetting the WHERE clause and unintentionally updating all rows; not handling NULL semantics or type conversions during updates.

Final Answer:
UPDATE