Why data sharing eliminates data copies in Snowflake - The Real Reasons

The Big Idea

What if you could share data without making endless copies that slow you down?

The Scenario

Imagine you have a big box of photos that you want to share with your friends. You make copies of the photos and send them to each friend separately. Now, every time you add a new photo or fix one, you have to make new copies and send them all over again.

The Problem

This copying process is slow and confusing. It wastes space because you have many copies of the same photos. Also, if you forget to update one copy, your friends might see old or wrong photos. Managing all these copies becomes a big headache.

The Solution

Data sharing lets you give your friends a direct link to your original photo box instead of sending copies. Everyone sees the same up-to-date photos without extra copies. This saves space, time, and keeps everything simple and accurate.

Before vs After

✗ Before

COPY INTO @friend1_stage FROM data;
COPY INTO @friend2_stage FROM data;

✓ After

CREATE SHARE friend1_share;
GRANT USAGE ON DATABASE your_database TO SHARE friend1_share;
CREATE SHARE friend2_share;
GRANT USAGE ON DATABASE your_database TO SHARE friend2_share;

What It Enables

It makes sharing fast, efficient, and always current without wasting storage or effort.

Real Life Example

A company shares live sales data with partners instantly without sending multiple files, so everyone works with the latest numbers.

Key Takeaways

Manual copying wastes time and space.

Data sharing provides direct access to original data.

It keeps data consistent and easy to manage.

Practice

1. What is the main reason data sharing in Snowflake eliminates the need for data copies?

easy

A. Because data is automatically deleted after sharing

B. Because users access the same data directly without duplicating it

C. Because data is encrypted before sharing

D. Because each user gets a personal copy of the data

Solution

1. Step 1: Understand data sharing concept

   Data sharing allows multiple users or accounts to access the same dataset without creating separate copies.

2. Step 2: Identify how data copies are avoided

   Since users query the shared data directly, no extra storage is used for duplicates.

3. Final Answer:

   Because users access the same data directly without duplicating it -> Option B

4. Quick Check:

   Data sharing = no data copies [OK]

Hint: Data sharing means one data source accessed by many [OK]

Common Mistakes:

• Thinking data is copied for each user
• Confusing encryption with data copying
• Assuming data is deleted after sharing

2. Which Snowflake object is used to share data without creating copies?

easy

A. Secure share

B. Database clone

C. Data warehouse

D. Stage

Solution

1. Step 1: Identify Snowflake sharing object

   Snowflake uses a 'secure share' object to share data securely without copying.

2. Step 2: Differentiate from other objects

   Database clones create copies; warehouses process queries; stages store files. Only secure shares share data without copies.

3. Final Answer:

   Secure share -> Option A

4. Quick Check:

   Secure share = data sharing without copies [OK]

Hint: Secure share shares data without copying it [OK]

Common Mistakes:

• Confusing clones with shares
• Thinking warehouses share data
• Mixing stages with data sharing

3. If Account A shares a table with Account B using Snowflake's data sharing, what happens when Account B queries the table?

medium

A. Account B queries a copy stored in its own storage

B. Account B must first copy the table to its account

C. Account B cannot query the table directly

D. Account B queries the original table in Account A's storage

Solution

1. Step 1: Understand shared table access

   When Account B queries a shared table, it accesses the original data stored in Account A's storage.

2. Step 2: Confirm no data copying occurs

   Snowflake's sharing avoids copying by letting Account B query data directly from Account A's storage.

3. Final Answer:

   Account B queries the original table in Account A's storage -> Option D

4. Quick Check:

   Shared data queried from original storage [OK]

Hint: Shared data is queried from original account storage [OK]

Common Mistakes:

• Assuming data is copied to Account B
• Thinking Account B must copy before querying
• Believing Account B cannot query shared data

4. A user tries to share a table but accidentally creates a clone instead. What is the main problem with this approach?

medium

A. The clone shares data without copying

B. The clone automatically deletes original data

C. The clone creates a full copy, using extra storage

D. The clone cannot be queried

Solution

1. Step 1: Understand difference between clone and share

   A clone creates a full copy of the data, which uses additional storage space.

2. Step 2: Identify the problem with cloning for sharing

   Cloning duplicates data, defeating the purpose of sharing without copies.

3. Final Answer:

   The clone creates a full copy, using extra storage -> Option C

4. Quick Check:

   Clone duplicates data, uses storage [OK]

Hint: Clone copies data; share does not [OK]

Common Mistakes:

• Thinking clone shares data without copying
• Believing clone cannot be queried
• Assuming clone deletes original data

5. How does Snowflake's data sharing ensure data consistency for all consumers without creating copies?

hard

A. By letting all consumers query the same live data in the provider's account

B. By copying data to each consumer and syncing changes regularly

C. By exporting data to external files for each consumer

D. By restricting access to only one consumer at a time

Solution

1. Step 1: Understand data consistency in sharing

   Snowflake shares data by allowing all consumers to query the same live data in the provider's account.

2. Step 2: Explain how copies affect consistency

   Copies can become outdated; sharing live data avoids this problem and keeps data consistent.

3. Step 3: Confirm no copies are made

   Since no copies are created, all consumers see the same up-to-date data instantly.

4. Final Answer:

   By letting all consumers query the same live data in the provider's account -> Option A

5. Quick Check:

   Live shared data keeps consistency [OK]

Hint: Shared live data keeps everyone consistent [OK]

Common Mistakes:

• Thinking data is copied and synced
• Assuming data is exported to files
• Believing only one consumer can access at a time