New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    Which SQL command is used to remove only specific rows

    from a table while preserving the structure and other rows?
    A DROP Correct Answer Incorrect Answer
    B TRUNCATE Correct Answer Incorrect Answer
    C DELETE Correct Answer Incorrect Answer
    D REMOVE Correct Answer Incorrect Answer
    E UPDATE Correct Answer Incorrect Answer

    Solution

    The DELETE command in SQL is used to remove specific rows from a table based on a WHERE clause condition. Unlike DROP or TRUNCATE, which impact the entire table, DELETE operates on a more granular level, enabling selective removal of data while preserving the table structure and any other rows. For example: DELETE FROM employees WHERE department = 'Sales'; This query removes only the rows from the employees table where the department is 'Sales', leaving all other rows intact. Additionally, the DELETE command logs each deleted row, making it possible to rollback transactions if the database supports it (e.g., in databases using transaction control). This makes DELETE particularly useful for scenarios where precision and rollback capabilities are required. Explanation of Incorrect Options: A) DROP : The DROP command is used to completely remove a table or database, including its structure. It is not selective and deletes the entire object. B) TRUNCATE : While TRUNCATE removes all rows from a table, it does not allow selective deletion. Furthermore, TRUNCATE is faster but does not log individual row deletions, making rollback impossible in most cases. D) REMOVE : This is not a valid SQL command. E) UPDATE : The UPDATE command is used to modify existing data, not to delete it.

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