COF-C03 Question 320
Single answerFail-safeA retail company stores order history in a permanent Snowflake table. An engineer accidentally executes a DELETE statement that removes all rows from the table. Eight days later, the team discovers the mistake and needs the data restored as quickly as possible. The table was not cloned, and there is no external backup. What is the BEST action to take?
- A
Use Time Travel to restore the table to a point before the DELETE statement.
- B
Open a Snowflake Support case to request recovery from Fail-safe.
- C
Query the table's micro-partitions directly because deleted data remains accessible for 90 days.
- D
Recreate the table structure and use UNDROP TABLE to recover the deleted rows.
Show answer and explanation
Correct answer: B
Explanation
This scenario tests the distinction between Time Travel and Fail-safe for permanent tables. Snowflake Time Travel allows customers to query, clone, or restore historical data within the retention period. After that period expires, the data enters a 7-day Fail-safe period for permanent objects. Fail-safe is designed for disaster recovery and is managed by Snowflake, not by the customer directly. Therefore, if the deletion is discovered after Time Travel has expired, the correct action is to contact Snowflake Support for possible recovery from Fail-safe. Best practice is to use Time Travel, zero-copy cloning, and data protection processes proactively because Fail-safe is slower, support-driven, and not intended for routine operational recovery.
- A. Incorrect.
Incorrect. Time Travel retention for permanent tables is limited and must still be within the configured retention period. After eight days, recovery through Time Travel is no longer available in a typical scenario where the standard retention has already expired. Once the data moves beyond Time Travel, it enters Fail-safe.
- B. Correct.
Correct. Fail-safe is intended as a last-resort recovery mechanism after the Time Travel retention period ends for permanent objects. Customers cannot directly query or restore data from Fail-safe themselves; they must contact Snowflake Support. This is the appropriate action when the loss is discovered after Time Travel has expired and the object is protected by Fail-safe.
- C. Incorrect.
Incorrect. Customers do not have direct access to micro-partitions for recovery purposes. Although Snowflake stores table data internally in micro-partitions, deleted data is not exposed for customer-driven recovery outside supported features such as Time Travel. Fail-safe recovery also cannot be performed by directly reading storage internals.
- D. Incorrect.
Incorrect. UNDROP TABLE is used to recover a dropped table within the Time Travel retention period, not to restore rows deleted by a DML statement. In this scenario, the table still exists and only its rows were deleted. Recreating the table would not recover the lost data.