What is Zero Copy Cloning in Snowflake?

Zero Copy Cloning is a special feature in Snowflake that allows you to make a copy (clone) of a database, schema, or table without copying all the data physically. This means:

• You can create a clone instantly
• The clone doesn’t take up extra storage space (until you change it)
• You can safely test, update, or experiment with data in the clone without affecting the original

It’s called “zero copy” because Snowflake does not create a new copy of the data when cloning. Instead, it shares the same storage as the original until changes are made.

 How Does It Work (In Simple Words)?

Imagine you have a document on your computer, and instead of copying the entire file, you create a link or shortcut. The file is not duplicated, but you can still use it. In Snowflake:

• The original table is like your file
• The clone is like a shortcut that can be used separately
• If you change the clone, only the changed parts are stored separately

This saves time, storage, and money.

 When to Use Zero Copy Cloning?

Here are some real situations where Zero Copy Cloning is helpful

1. Testing New Code or Queries
   • You want to try a new SQL query or script but don’t want to change the original data.
   • Clone the table or database, run your queries, and test safely.
2. Creating a Backup
   • Need a quick backup before changing something? Clone it first.
3. Training or Demos
   • You can clone data for internal training or demos without sharing real data.
4. Development Environments
   • Create dev or QA environments instantly using clones.

Step-by-Step Process to Create a Zero Copy Clone

 Step 1: Log into Snowflake

• Open the Snowflake UI in your browser.
• Or use a SQL editor like SnowSQL, VS Code, DBeaver, or any BI tool.
• Use your login credentials.

Step 2: Decide What You Want to Clone

You can clone

Object	Description
Table	Only one table is cloned
Schema	All tables and views in a schema are cloned
Database	The entire database (schemas, tables, procedures) is cloned

Tip: You should only clone what you need. Cloning a full database takes more time and includes everything.

 Step 3: Write the Clone Command

The command structure is CREATE <object_type> <new_name> CLONE <original_object>;

 Clone a Table

CREATE TABLE orders_clone CLONE orders;

 Clone a Schema

CREATE SCHEMA finance_clone CLONE finance;

 Clone a Database

CREATE DATABASE company_backup CLONE company_data;

 Step 4: (Optional) Use Time Travel

Time Travel allows you to clone old versions of your data using a specific time or offset.

Clone Table As It Was Yesterday

CREATE TABLE orders_yesterday CLONE orders AT (OFFSET => -1);

 Clone at a Specific Timestamp

CREATE TABLE orders_old CLONE orders AT (TIMESTAMP => '2024-12-31 10:00:00'); Useful when you want to recover deleted rows or view data from the past.

 Step 5: Use the Clone as You Like

Once the clone is created, you can

• Run select, insert, update, and delete queries
• Add or remove columns
• Rename the clone
• Use it in reports or dashboards

Changes to the clone do NOT affect the original data.

 Step 6: Modify or Test Safely

If you

• Write test queries
• Update rows
• Change data

➡ Only those changes take up new space. Everything else still refers to the original. This is why it’s cost-efficient.

 Step 7: Drop the Clone When Done

To remove the clone and free up space DROP TABLE orders_clone;DROP SCHEMA finance_clone;DROP DATABASE company_backup The original data remains safe. Only the clone is removed.

 Behind the Scenes – How It Saves Space

When you clone something in Snowflake

• The metadata (structure) is copied
• The data is shared, not duplicated
• Any new changes in the clone are saved separately

This is known as Copy-on-Write: the original stays the same unless you modify something in the clone.

 Real-Life Example

Use Case: A data team wants to run monthly sales analysis using the current month’s data.

1. They clone the database sales_data as sales_data_april.
2. Analysts run experiments, build reports on sales_data_april.
3. The main database sales_data remains untouched.
4. When done, they drop sales_data_april.

No extra data storage unless they make changes No risk to the main data Fast and low-cost

The Challenges in Traditional Cloning Methods

Cloning means making a copy of your data, like a backup or a duplicate. Before advanced tools like Snowflake’s Zero Copy Cloning, many companies used traditional cloning methods. These older methods had many problems and limitations.

 1. Takes a Lot of Time

In traditional systems

• If you want to copy a large table or full database, it can take many minutes or even hours.
• You have to wait until the entire copy is done before you can start using it.

Simple Example Imagine copying a big folder of 10,000 photos from your phone to your laptop. It takes time, right? Same with big databases — traditional cloning was slow.

 2. Uses More Storage Space

Every clone in the traditional system

• Takes up separate physical space on disk
• Means double storage if you make just one copy
• Even more space if you make multiple copies for testing, backup, etc.

Simple Example If your original table is 100 GB, each clone takes another 100 GB. So 3 clones = 300 GB extra used. This increases storage cost very fast.

 3. Very Expensive

Because you

• Use more storage
• Use more compute time
• Use more server resources

The total cost becomes high — especially if you need regular clones for testing or backups. Companies with big data spend a lot of money to manage this cloning manually.

 4. Hard to Keep Clones Updated

Let’s say

• You cloned a table on Monday
• Then the original table gets new data on Tuesday

Your clone will not have Tuesday's data unless you manually update it. This leads to

• Outdated copies
• Manual syncing
• Confusion about what data is latest

Syncing clones manually becomes a regular headache for teams.

5. High Risk of Errors

In traditional cloning:

• Someone may accidentally update the original data while working on the clone
• Or may forget which copy is the latest version
• Developers may test code on the real database by mistake

These mistakes can cause data loss or wrong results.

 6. Security and Access Issues

Each clone may need

• New user access setup
• New permissions
• You must manually check who can see or change the data

If you forget, someone might

• Access sensitive data
• Or make unauthorized changes

Managing permissions for every clone can be very hard and risky.

 7. Not Good for Testing

Developer  often need test data. But traditional cloning:

• Is slow
• Costs more
• Needs cleanup after use

So

• Testers sometimes skip cloning and test directly on production data
• This can crash systems or damage real data

You also need to delete old test data manually, which is another time-consuming task.

 8. Manual Work and Complex Steps

To create a clone in traditional systems, you often had to

• Write complex backup scripts
• Use tools to export/import data
• Schedule time windows to avoid system load

This process is

• Manual
• Boring
• Time-consuming

And sometimes things break during cloning!

 9. Difficult Rollback

If something goes wrong during cloning or testing

• Going back to the previous version is hard
• You may lose data if backup is not recent

In some systems, there’s no undo or time travel. This can be risky for important data.

 10. Performance Impact

Cloning a big database or table in a traditional system can

• Slow down the server
• Affect users who are running live reports
• Cause system crashes

Because the system is busy copying huge data, other jobs get delayed.

Benefits of Zero Copy Cloning in Snowflake

Zero Copy Cloning is a special feature in Snowflake that helps you create a copy of your data without actually copying the whole data. It saves a lot of time, money, and effort.  

Saves Storage Space

In normal systems, every time you make a copy, it uses extra space. But with Zero Copy Cloning

• No extra storage is used at first.
• It uses the same data as the original.
• Only new changes (if any) take up extra space.

Example If you clone a 100 GB table, Snowflake doesn’t create another 100 GB copy. It just points to the same data. So it uses almost zero extra space.  

Very Fast Cloning

Zero Copy Cloning is super quick because

• It doesn’t actually copy any data.
• It just creates a reference to the original data.

You can clone a large table or database in just seconds. Traditional systems can take hours, but Zero Copy Cloning is almost instant.  

Saves Money

Because it

• Uses less storage
• Doesn’t need extra compute power
• Needs less manual effort

It reduces your total cost. No need to pay for extra storage or slow backup tools.  

Great for Testing

Developers and testers often need a copy of real data. With Zero Copy Cloning

• They can get a clone instantly.
• They can test without touching real data.
• They can delete the clone easily after use.

This makes testing safer, faster, and cheaper.

Easy Rollback and Recovery

If you

• Delete data by mistake
• Or change something wrongly

You can use Zero Copy Cloning to

• Go back to the older version
• Quickly recover your data

It’s like a backup, but much easier to use.  

No Impact on Original Data

When you work on the clone

• The original data stays safe.
• You can test or make changes on the clone.
• No risk to production data.

This keeps your real data safe and untouched.  

 Simple to Use

To make a clone, you only need one line of SQL CREATE CLONE my_table_copy FROM my_table No need for complex tools or scripts. Even beginners can do it easily. Works with Many Objects You can use Zero Copy Cloning for

• Tables
• Schemas
• Databases

So it’s very flexible and fits many use cases.

Supports Time Travel

You can also

• Clone your table as it looked yesterday
• Or a few hours ago

Using Time Travel with cloning makes it even more powerful. This helps in auditing and fixing mistakes.

Better Performance

Since cloning is fast and light

• It doesn’t slow down your system
• Your live reports or dashboards don’t get affected

Other users can keep working while you make clones.

Improves Collaboration

Teams can

• Work on clones
• Share with others safely
• Avoid messing with the real data

It makes working in teams easier and more organized.

What Happens If You Clone a Clone in Snowflake?

 First, Let’s Understand: What Is Cloning in Snowflake?

In Snowflake, cloning means making a copy of a database, schema, or table. But the special part is: this copy is not physical. It’s logical.

That means

• You don’t copy the entire data physically.
• Snowflake creates a reference to the original data.
• This type of cloning is called Zero Copy Cloning.
• It’s very fast, uses very little extra space, and is great for testing or backups.

 

 Now, The Big Question: What Happens If You Clone a Clone?

Let’s say

1. You have a main tablecalled customer_orders.
2. You create a clone of it, named customer_orders_clone1.
3. Then you create another clonefrom that clone, called customer_orders_clone2.

The Answer is: Yes

Even the second clone (or third, or fourth...) still refers to the same original data in the background. So, you can keep cloning clones, and it still works the same way.  

 How Snowflake Handles This Internally

When you make a clone

• Snowflake just creates a pointer or reference to the same data blocks.
• It does not copy the data physically.
• So even if you clone a clone, all clones are still connected to the original data.

Only when you make changes, Snowflake stores the changed data separately. This is called Copy-on-Write behavior

• Data is only copied when it is written or changed.

 

 Example to Understand Better

Let’s say you have this original table CREATE TABLE product_data (product_id INT, name STRING); Then you create clones CREATE TABLE product_data_clone1 CLONE product_data;CREATE TABLE product_data_clone2 CLONE product_data_clone1; Now you have three tables

• All three tables share the same data at the beginning.
• If you don’t make any changes, no extra space is used.

If you update a row in product_data_clone2, only that specific row is stored separately. The rest of the data is still shared with the original.  

 Important Points to Remember

1.  Yes, You Can Clone a Clone

Snowflake allows it. It works the same way as cloning the original.

2.  All Clones Use the Same Base Data

All clones still connect to the original data in the background.

3.  Storage is Not Duplicated

As long as you don’t change the data, clones don’t take extra storage.

4.  If You Change a Clone

Only the changed part is stored. The rest still uses shared storage.

5.  Useful for Testing

You can create multiple clones for different teams, projects, or testing purposes.

 

CREATE DATABASE sales_teamA CLONE sales_data;CREATE DATABASE sales_teamB CLONE sales_teamA;CREATE DATABASE sales_teamC CLONE sales_teamB; Each team has their own copy, but no extra storage is used (unless someone makes a change).  

 Is It Safe to Clone a Clone?

Yes! It’s 100% safe.

• You can delete any clone without affecting the original or other clones.
• You can make changes in the clone without affecting the original.
• Each clone is independent after it’s created.

Types of Zero Copy Cloning in Snowflake

In Snowflake, you can clone different kinds of objects. These are the types of cloning based on what you are cloning

 A. Database Cloning

You can clone an entire database. This means all schemas, tables, views, and other objects inside the database are copied — without actually using extra space.

CREATE DATABASE sales_clone CLONE sales

Use this when you want to test or back up a full database.

 B. Schema Cloning

A schema is a part inside a database that contains tables and views.
You can clone just one schema if you don’t need the whole database.

CREATE SCHEMA orders_clone CLONE sales.orders;

 This is useful if you want to test or modify just one section of your data.

 C. Table Cloning

You can also clone a single table. This will copy the table’s structure and data — without using extra space.

CREATE TABLE customer_clone CLONE sales.customers;

 Helpful when you need to try changes on a table without touching the original.

 D. Cloning Views and Other Objects

You can also clone

• Views
• Streams
• Tasks
• Stages (external/internal)

This helps when you want a full working copy of your project setup.

 2. Use Cases for Zero Copy Cloning

Let’s now look at some real-life examples where Zero Copy Cloning is useful.

 A. Testing and Development

Developers often need a copy of real data to test their code.

Instead of copying huge data, you can create a clone, test your changes, and delete the clone later.

This saves time, cost, and reduces errors.

 B. Backup Before Changes

Before running a risky SQL command like delete or update, you can create a clone of the table.

If something goes wrong, you can go back to the clone.

It’s like taking a snapshot or backup — instantly

 C. Running What-If Scenarios

Imagine your team wants to check:

“What if we give a 10% discount on all orders?”

Instead of changing real data, clone the table and apply the logic.

This helps in analysis without risk.

 D. Data Science and Machine Learning

Data scientists need full data to train their models.

Using a clone

• They get a copy instantly
• No one else is affected
• No delay or extra cost

It’s a perfect fit for safe experiments.

 E. Training and Demos

Trainers and companies use clones to create practice environments.

Everyone can get their own copy without copying actual data physically.

 F. Creating Environments (Dev, QA, UAT)

You can create different environments like:

• Dev (Development)
• QA (Testing)
• UAT (User Acceptance Testing)

Using clones, all teams get real-like data without waiting for long setup.

 G. Time Travel with Cloning

Using Time Travel, you can even create a clone from the past.

Example: Get yesterday’s version of a table.

CREATE TABLE yesterday_data CLONE sales.orders AT (OFFSET => -1);

This helps in data recovery or analysis of old versions.

 3. Limitations and Considerations

While Zero Copy Cloning is very powerful, it also has some limits and things to remember.

 A. Clones Are Still Linked to the Original

At the start, cloned objects share the same data blocks as the original.
But if you change something, then extra space is used.

So, many changes in clones will use more storage.

 B. Time Travel Limit Applies

You can create a clone using Time Travel only within the allowed time window (default is 1 day, max 90 days with paid plan).

After that, the older version cannot be cloned.

 C. No Cross-Account Cloning

You can’t clone data between two different Snowflake accounts.
If you need to move data to another account, you must export and import.

 D. Cloning Is Instant, But Not Always Free

Creating a clone is free if you don’t change it.
But once you start writing or updating data, it starts using space, which might cost money.

 E. Dependency Issues

If you clone a schema or database, the permissions and access controls might need to be set again.

Snowflake doesn’t always carry all grants and roles to the clone.

F. Some Objects Cannot Be Cloned

Certain objects, like

• File formats
• External functions
• Resource monitors

may not be cloneable. You’ll have to create those manually

 

The Future of Data Cloning

 Introduction: What Is Data Cloning?

Data cloning means creating an exact copy of data from one place to another. In modern technology, this is used for

• Backups
• Testing new features
• Data analysis
• Sharing data safely

With cloud systems like Snowflake, data cloning has become faster, cheaper, and easier. Now, let’s explore what the future holds for data cloning and how different technologies, events, and opinions shape it.

 

 The Future of Data Cloning

The future of data cloning looks very promising. New tools are making it more powerful and smarter. Here are some possible changes we can expect:

 1. Faster and Smarter Cloning

Data cloning will become much faster. Instead of copying all data, tools will use smart cloning — where only the changes are copied. This saves time and storage.

 2. Real-Time Cloning

Soon, data cloning might happen in real-time. That means any update to the original data is quickly reflected in the clone. This is great for systems that need live testing or reports.

 3. Cloning Across Clouds

Right now, cloning is mostly done within the same cloud or system. In the future, we might be able to clone data across multiple cloud platforms (like AWS, Azure, and Google Cloud).

 4. More Secure Cloning

Security will become a big part of cloning. Future cloning tools will make sure that only the right people can access the cloned data. Features like:

• Data masking
• Auto-expiring access
• Smart permissions
  will become common.

 

 Diverse Perspectives on Data Cloning

Different people and industries have different opinions about data cloning. Let’s look at some of these views.

 1. Business Leaders

Business people love data cloning because:

• It helps teams work faster
• Reduces downtime
• Supports faster decision-making

They see cloning as a cost-saving tool.

 2. Data Scientists

Data scientists use cloning to test models safely. They can clone real data and train their AI models without affecting the original data. This makes their work faster and more reliable.

 3. Developers

For developers, cloning is useful because they can:

• Try new features
• Fix bugs
• Test updates
  without breaking the live data.

They see cloning as a safe playground.

 4. Security Experts

Security experts support cloning — but with warnings. They want rules to ensure cloned data is not misused. Their focus is on:

• Data privacy
• Access control
• Limiting sensitive data exposure

 

 Data Cloning and Artificial Intelligence (AI)

AI and data cloning go hand in hand. Let’s see how cloning helps AI and how AI improves cloning.

 A. How Data Cloning Helps AI

AI systems need lots of training data. But using live data can be risky. With data cloning:

• AI teams can create safe training copies
• Try multiple experiments
• Improve accuracy without harming the real system

 B. How AI Improves Data Cloning

AI tools can make data cloning smarter:

• AI can decide what data to clone
• Avoid copying extra or unused data
• Detect if cloned data has errors

In the future, AI-powered cloning will make systems faster, cheaper, and safer.

 

 The Impact of COVID-19 on Data Cloning

The COVID-19 pandemic changed the way businesses work. It pushed many companies to move online and adopt cloud technologies. Here’s how COVID-19 affected data cloning:

 1. More Demand for Cloud Data

With remote work, businesses started using cloud systems more. This created more need for:

• Secure data access
• Fast testing environments
• Sharing data with teams safely

Cloning became a key part of handling all this.

 2. Faster Software Development

Companies wanted to build digital tools quickly. They used data cloning to:

• Speed up testing
• Create safe backup copies
• Try new features quickly

 3. Focus on Security

During COVID-19, data breaches increased. Companies started using cloning with better security rules, like:

• Hiding personal info in clones
• Setting automatic deletion times
• Using clone logs to track access

 4. Continuity and Recovery

Some companies used clones as part of their disaster recovery plans. If systems failed due to the crisis, cloned data helped them bounce back quickly.

 Challenges and Considerations in the Future

Even though the future of data cloning is bright, there are a few challenges to think about.

 1. Data Privacy Rules

Cloned data should still follow rules like:

• GDPR (Europe)
• HIPAA (Health data in the US) If companies ignore these, they could face big fines.

 2. Storage Overuse

Too many clones can eat up storage. Companies must track:

• Who made the clones
• How long they are needed
• When to delete them

 3. Cost Management

While cloning can be cheap at first, large and unused clones can become expensive over time.

 4. Human Error

If someone clones the wrong version of data or gives access to the wrong team — it could lead to problems. Clear rules and training are needed.

Conclusion

Data cloning is not just a copy tool. It's a smart, safe, and powerful method to

• Work faster
• Test better
• Protect your original data

In the future, we will see

• Real-time cloning
• Smart AI-powered decisions
• Safe cross-cloud copies

Different industries and experts support data cloning, but they also ask for:

• Strong security
• Privacy rules
• Smart cost control

Thanks to lessons learned during COVID-19, businesses now understand the value of cloning more than ever. It's becoming an important part of digital growth.

In short: The future of data cloning is smart, safe, and full of possibilities.