In today’s globalized business environment, managing time zones in Snowflake is no longer optional—it’s essential. Whether you’re analyzing data for teams in New York, London, Tokyo, Sydney, or Mumbai, understanding how Snowflake handles timestamps ensures your queries are accurate, your dashboards are reliable, and your data pipelines function seamlessly. Snowflake Timezones: A Complete Global Guide.
In this comprehensive guide, we’ll walk you through Snowflake timezones from beginner to advanced levels, covering account and session settings, timestamp types, timezone conversions, and best practices for global data management.
Why Snowflake Timezones Matter
Imagine this scenario: A sales report is generated at 8 AM in New York but your team in Tokyo sees it at 10 PM. Without proper timezone handling, data can appear inconsistent, leading to mistakes in analytics, reporting, and business decisions.
Proper timezone management in Snowflake ensures:
- Accurate cross-region analytics dashboards
- Correct scheduled tasks and data pipelines
- Consistent data storage and retrieval globally
- Reliable timestamped logs for audits
Understanding Snowflake Timestamp Types
Snowflake uses three primary timestamp types, each with different timezone behavior:
| Timestamp Type | Storage | Display Behavior | Use Case |
|---|---|---|---|
| TIMESTAMP_NTZ | No timezone | Displayed in session timezone | Raw data ingestion, regional processing |
| TIMESTAMP_LTZ | UTC | Converts to session timezone | Multi-region reporting, event tracking |
| TIMESTAMP_TZ | UTC + timezone info | Retains original timezone, converts automatically | Multi-region events, logs, audit trails |
Expert Tip: For global applications, prefer TIMESTAMP_LTZ or TIMESTAMP_TZ to maintain consistency across regions.
Snowflake Timezone Settings
1. Account Timezone
The default timezone for all sessions in an account. Set this for a central reference point.
ALTER ACCOUNT SET TIMEZONE = 'America/New_York';
2. Session Timezone
Overrides the account timezone for the current session. Useful for personalized dashboards.
ALTER SESSION SET TIMEZONE = 'Asia/Tokyo';
3. Object-Level Timezone
When inserting timestamps with timezone info, Snowflake converts them automatically:
INSERT INTO sales VALUES (1, '2026-01-27 08:00:00+09:00');
Converting Timezones in Snowflake
Snowflake provides functions to manage and convert timestamps.
CONVERT_TIMEZONE
SELECT CONVERT_TIMEZONE('America/New_York', 'Asia/Tokyo', CURRENT_TIMESTAMP);
- Converts a timestamp from one timezone to another.
- Handles Daylight Saving Time automatically.
CURRENT_TIMESTAMP with Session Timezone
ALTER SESSION SET TIMEZONE = 'Europe/London';
SELECT CURRENT_TIMESTAMP;
- Displays current time according to the session timezone. Snowflake Timezones: A Complete Global Guide.
Handling Daylight Saving Time
DST can cause discrepancies in reports if overlooked. Snowflake manages DST automatically for named timezones like 'America/New_York'. Avoid numeric offsets like +05:30 if your data spans regions with DST.
Practical Examples
Example 1: Multi-Region Sales Report
SELECT
sale_id,
sale_time,
CONVERT_TIMEZONE('UTC', 'America/Los_Angeles', sale_time) AS pacific_time,
CONVERT_TIMEZONE('UTC', 'Asia/Tokyo', sale_time) AS tokyo_time
FROM sales;
- Ensures teams in LA and Tokyo see consistent sales data in their local time.
Example 2: Scheduled Data Load
ALTER SESSION SET TIMEZONE = 'UTC';
INSERT INTO analytics_load VALUES (CURRENT_TIMESTAMP);
- Maintains consistency for scheduled ETL jobs across multiple regions.
Best Practices for Snowflake Timezones
- Always store timestamps in UTC: Standardizes data across regions.
- Use TIMESTAMP_TZ for global events: Retains original timezone information.
- Set session timezone for users: Personalizes dashboards and queries.
- Convert timestamps for reporting: Use
CONVERT_TIMEZONE()for multi-region dashboards. - Document account and session defaults: Reduces confusion in large teams.
- Prefer named timezones over offsets: Handles DST correctly.
- Audit multi-region logs with timezone info: Ensures reliability in distributed systems.
Advanced Tips
- Leverage session variables for multi-region scripts:
SET region = 'America/New_York';
SELECT CONVERT_TIMEZONE($region, 'Asia/Tokyo', CURRENT_TIMESTAMP);
- Audit logs: Include timezone metadata to maintain clarity.
- Avoid mixing numeric offsets with named timezones: Prevents DST-related errors.
Frequently Asked Questions (FAQ)
Q1: What is the difference between TIMESTAMP_NTZ and TIMESTAMP_TZ?
A: TIMESTAMP_NTZ has no timezone info, while TIMESTAMP_TZ retains explicit timezone data.
Q2: Should I store timestamps in UTC or local time?
A: Always store in UTC; convert to local timezone for display using session or query functions.
Q3: How does Snowflake handle Daylight Saving Time?
A: Named timezones (e.g., ‘America/New_York’) automatically adjust for DST.
Q4: Can I change the timezone for a specific user session?
A: Yes, set the session timezone using ALTER SESSION SET TIMEZONE = '<zone>'.
Q5: How do I display the current time in a specific timezone?
A: Use CONVERT_TIMEZONE() or set session timezone and call CURRENT_TIMESTAMP.
Actionable Checklist
- Store all timestamps in UTC
- Use TIMESTAMP_TZ for global events
- Set session timezone per user
- Convert timestamps for dashboards with
CONVERT_TIMEZONE() - Document all account and session timezone defaults
- Use named timezones for DST handling
- Audit multi-region data with timezone metadata. Snowflake Timezones: A Complete Global Guide.
Conclusion
Mastering Snowflake timezones is essential for accurate analytics, smooth operations, and effective global collaboration. By understanding timestamp types, session settings, and timezone conversions, you can ensure teams in New York, London, Tokyo, Sydney, Mumbai, and beyond work with reliable data, free from confusion and errors.
Proper timezone management in Snowflake improves reporting accuracy, reduces errors, and ensures your global data strategy runs efficiently and seamlessly.
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