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Answer: Use time travel feature to refer old data instead of manually copying
The correct answer is to use the time travel feature to refer to old data instead of manually copying. This feature allows you to query previous versions of your data without the need for manual backups. For more information, you can refer to the Delta Lake documentation on time travel: [Introducing Delta Time Travel for Large-Scale Data Lakes](https://databricks.com/blog/2019/02/04/introducing-delta-time-travel-for-large-scale-data-lakes.html). Example queries include: `SELECT count(*) FROM my_table TIMESTAMP AS OF '2019-01-01'`, `SELECT count(*) FROM my_table TIMESTAMP AS OF date_sub(current_date(), 1)`, and `SELECT count(*) FROM my_table TIMESTAMP AS OF '2019-01-01 01:30:00.000'`.
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Your colleague is manually copying data to a backup folder before running an update command, as a precaution in case the update doesn't yield the expected results. Which Delta Lake feature would you recommend to simplify this process?
A
Use DEEP CLONE to clone the table prior to update to make a backup copy
B
Use SHADOW copy of the table as preferred backup choice
C
Cloud object storage retains previous version of the file
D
Cloud object storage automatically backups the data
E
Use time travel feature to refer old data instead of manually copying