Creating tables (permanent, temporary, transient) in Snowflake - Practice Exercises

Challenge - 5 Problems

🧠 Conceptual

intermediate

Difference in data retention for table types

Which type of Snowflake table retains data even after the user session ends and supports Time Travel and Fail-safe features?

A Temporary table

B Transient table

C External table

D Permanent table

💡 Hint

Think about which table type is designed for long-term storage with full data protection.

Permanent tables store data persistently and support Time Travel and Fail-safe. Temporary tables exist only during the session. Transient tables skip Fail-safe. External tables reference external storage.

❓ service_behavior

intermediate

Session scope of temporary tables

What happens to a temporary table in Snowflake when the user session that created it ends?

A The temporary table is automatically dropped and data is lost.

B The temporary table persists and can be accessed by other sessions.

C The temporary table is converted to a permanent table.

D The temporary table is archived for 7 days.

💡 Hint

Consider the lifespan of temporary tables relative to user sessions.

Temporary tables exist only during the session that created them. When the session ends, the table and its data are dropped automatically.

❓ Configuration

advanced

Creating a transient table with clustering

Which SQL statement correctly creates a transient table named sales_data with clustering on the region column?

A CREATE TABLE TRANSIENT sales_data (id INT, region STRING) CLUSTER ON region;

B CREATE TRANSIENT TABLE sales_data (id INT, region STRING) CLUSTER BY (region);

C CREATE TRANSIENT TABLE sales_data (id INT, region STRING) CLUSTERED BY region;

D CREATE TRANSIENT TABLE sales_data (id INT, region STRING) CLUSTER BY region;

💡 Hint

Check the correct syntax for clustering keys in Snowflake table creation.

The correct syntax uses CLUSTER BY (column_name) after the column definitions. Option B matches this syntax exactly.

❓ security

advanced

Data protection differences between permanent and transient tables

Which statement correctly describes the difference in data protection features between permanent and transient tables in Snowflake?

A Permanent tables support Time Travel and Fail-safe, transient tables do not support Fail-safe.

B Permanent tables support Time Travel and Fail-safe, transient tables support only Time Travel.

C Transient tables support Time Travel and Fail-safe, permanent tables do not.

D Both permanent and transient tables do not support Fail-safe.

💡 Hint

Recall which table type skips Fail-safe to reduce storage costs.

Permanent tables support both Time Travel and Fail-safe. Transient tables support Time Travel but skip Fail-safe, reducing storage costs but lowering data protection.

❓ Architecture

expert

Choosing table type for temporary session data with no recovery needs

You need to store intermediate data during a user session that should be automatically removed when the session ends. The data does not require Time Travel or Fail-safe. Which table type should you choose?

A External table

B Transient table

C Temporary table

D Permanent table

💡 Hint

Consider the table type that exists only during the session and does not keep data after.

Temporary tables exist only during the session and are dropped automatically afterward. They do not support Time Travel or Fail-safe, making them ideal for temporary session data.

Practice

1. Which type of table in Snowflake is best suited for storing data that needs to persist permanently and be recoverable after accidental deletion?

easy

A. TEMPORARY table

B. PERMANENT table

C. TRANSIENT table

D. EXTERNAL table

Solution

1. Step 1: Understand table types in Snowflake

   Permanent tables store data permanently and include fail-safe for recovery.

2. Step 2: Compare with other table types

   Temporary tables last only for the session, and transient tables do not have fail-safe, so they are not recoverable after deletion.

3. Final Answer:

   PERMANENT table -> Option B

4. Quick Check:

   Permanent = long-term, recoverable [OK]

Hint: Permanent tables keep data safe and recoverable long-term [OK]

Common Mistakes:

• Confusing transient with permanent tables
• Thinking temporary tables persist beyond session
• Assuming transient tables have fail-safe

2. Which of the following is the correct syntax to create a temporary table named session_data with columns id INT and value STRING in Snowflake?

easy

A. CREATE TABLE session_data TEMPORARY (id INT, value STRING);

B. CREATE TABLE TEMP session_data (id INT, value STRING);

C. CREATE TEMPORARY TABLE session_data (id INT, value STRING);

D. CREATE TEMP session_data (id INT, value STRING);

Solution

1. Step 1: Recall Snowflake syntax for temporary tables

   The correct keyword is TEMPORARY placed right after CREATE and before TABLE.

2. Step 2: Check each option's syntax

   CREATE TEMPORARY TABLE session_data (id INT, value STRING); uses correct order and keywords. Options A, B, and C use incorrect or unsupported syntax.

3. Final Answer:

   CREATE TEMPORARY TABLE session_data (id INT, value STRING); -> Option C

4. Quick Check:

   CREATE TEMPORARY TABLE = correct syntax [OK]

Hint: Use CREATE TEMPORARY TABLE for temporary tables [OK]

Common Mistakes:

• Using TEMP instead of TEMPORARY
• Placing TEMPORARY after table name
• Omitting TABLE keyword

3. What will be the result of the following Snowflake SQL commands?

CREATE TRANSIENT TABLE temp_cost (item STRING, price NUMBER);
INSERT INTO temp_cost VALUES ('apple', 1.2);
SELECT * FROM temp_cost;

medium

A. Syntax error due to TRANSIENT keyword

B. Error: Table does not exist

C. Empty result set

D. [{'item': 'apple', 'price': 1.2}]

Solution

1. Step 1: Understand transient table behavior

   Transient tables behave like permanent tables but without fail-safe. They accept inserts and can be queried normally.

2. Step 2: Analyze the commands

   The table is created, a row is inserted, and then selected. No errors or empty results expected.

3. Final Answer:

   [{'item': 'apple', 'price': 1.2}] -> Option D

4. Quick Check:

   Transient tables store and return inserted data [OK]

Hint: Transient tables act like permanent but no fail-safe [OK]

Common Mistakes:

• Thinking transient tables cannot store data
• Expecting syntax error with TRANSIENT keyword
• Assuming transient tables auto-delete data immediately

4. You run the following command in Snowflake:

CREATE TEMPORARY TABLE temp_users (user_id INT, name STRING);

Later, you try to query temp_users in a new session but get an error. What is the most likely cause?

medium

A. Temporary tables only exist during the session they were created in

B. Syntax error in table creation

C. Transient tables cannot be queried

D. Table was dropped manually

Solution

1. Step 1: Recall temporary table lifecycle

   Temporary tables exist only for the duration of the session that created them.

2. Step 2: Understand session behavior

   Querying in a new session fails because the temporary table no longer exists.

3. Final Answer:

   Temporary tables only exist during the session they were created in -> Option A

4. Quick Check:

   Temporary = session-only lifespan [OK]

Hint: Temp tables vanish after session ends [OK]

Common Mistakes:

• Assuming temp tables persist across sessions
• Confusing transient with temporary tables
• Ignoring session scope of temporary tables

5. You want to create a table in Snowflake that stores temporary data across sessions but does not use fail-safe to reduce storage costs. Which table type and creation statement should you use?

hard

A. CREATE TRANSIENT TABLE cost_savings (id INT, amount NUMBER);

B. CREATE TEMPORARY TABLE cost_savings (id INT, amount NUMBER);

C. CREATE PERMANENT TABLE cost_savings (id INT, amount NUMBER);

D. CREATE EXTERNAL TABLE cost_savings (id INT, amount NUMBER);

Solution

1. Step 1: Identify table types and fail-safe behavior

   Transient tables do not have fail-safe, reducing storage costs but keep data beyond session.

2. Step 2: Match requirement with table type

   Temporary tables are session-only, permanent tables have fail-safe, external tables are for external data.

3. Final Answer:

   CREATE TRANSIENT TABLE cost_savings (id INT, amount NUMBER); -> Option A

4. Quick Check:

   Transient = no fail-safe, cost-saving [OK]

Hint: Use transient tables to save costs without fail-safe [OK]

Common Mistakes:

• Choosing temporary tables which expire after session
• Using permanent tables with fail-safe enabled
• Confusing external tables with transient