Snowflake Data Recovery Explained ❄️ Time Travel, Fail-safe & Restore

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Snowflake Data Recovery Explained ❄️ Time Travel, Fail-safe & Restore

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Snowflake Data Recovery Explained ❄️ Time Travel, Fail-safe & Restore

Arabinda Mohapatra

Arabinda Mohapatra

Running Kafka streams after dark, diving into genetic code by daylight, and wrestling with Databricks and Tableflow in every spare moment—sleep is optional

⏳ Time Travel, Fail-safe & Data Recovery in Snowflake — Explained Deeply ❄️

Snowflake doesn’t update data in place. Every change creates new micro-partitions, and recovery depends entirely on Time Travel & Fail-safe configuration.


🧠 Time Travel (User-Controlled Recovery)

Time Travel allows you to:

  • Query historical data
  • Restore dropped objects
  • Clone tables at a past point in time

🔍 Query past data 

SELECT * 
FROM orders 
AT (TIMESTAMP => '2026-01-30 10:00:00');

or 

SELECT * 
FROM orders 
BEFORE (STATEMENT => '01b3c9a7-0000-1234');

♻️ Restore a dropped table (most common use case) 

UNDROP TABLE orders;

Works only if:

  • Table is within Time Travel retention
  • Object type supports Time Travel

🧬 Clone from a previous state 

CREATE TABLE orders_restore 
CLONE orders 
AT (TIMESTAMP => '2026-01-30 10:00:00');

✅ Zero-copy ✅ Instant ✅ No extra compute

🛟 Fail-safe (Snowflake-Controlled Recovery)

Fail-safe is the last safety net:

  • 7 days
  • Not queryable
  • Only Snowflake Support can restore
  • Available only for Permanent tables

🚫 No SQL commands here 👉 You must raise a Snowflake support ticket

📊 Table Types — Recovery Behavior (Snowflake Standpoint)

Permanent Tables

  • Time Travel + Fail-safe
  • SQL restore supported
  • Best for production & compliance data

UNDROP TABLE prod_orders;

Transient Tables

  • Time Travel only (0–1 day)
  • ❌ No Fail-safe
  • After retention → data permanently lost

UNDROP TABLE stage_orders; -- works only within Time Travel window

Temporary Tables

  • Session-based
  • Auto-dropped at session end
  • Retention = 24 hours OR session end (whichever is earlier)

⚠️ Once session ends → restore not possible

⏳ Important Internal Behavior

  • Long-running Time Travel queries delay physical purge
  • Applies to temporary & transient tables
  • Prevents broken reads during recovery

⚠️ Cost vs Safety (Critical Insight)

Fail-safe storage costs money. That’s why Snowflake gives you Transient tables.

But remember:

Once Time Travel expires on a transient table, data is gone forever — even Snowflake can’t recover it.

Snowflake gives you multiple recovery layers, but you must design intentionally.

REfer-https://docs.snowflake.com/en/user-guide/data-time-travel




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