Snowflake COF-C02 - SnowPro Core Certification Exam

The correct answer is B. Loading and unloading data .

SnowSQL is Snowflake’s command-line client. It is used to connect to Snowflake, execute SQL statements, run SQL scripts, and perform data loading and unloading operations.

Why B is correct:

SnowSQL supports data loading and unloading workflows. For example, users can use SnowSQL to run PUT, GET, and COPY commands.

Example loading workflow:

PUT file:///local/path/data.csv @my_stage;

COPY INTO my_table

FROM @my_stage

FILE_FORMAT = (TYPE = CSV);

Example unloading workflow:

COPY INTO @my_stage/output/

FROM my_table;

GET @my_stage/output/ file:///local/path/output/;

Why the other options are incorrect:

A. Dashboards are usually developed in BI tools or applications, not SnowSQL.

C. Snowflake Native Apps are developed and managed using Snowflake Native App Framework tools and Snowflake CLI, not primarily SnowSQL.

D. Monitoring transformation activity is usually done through Snowflake views, query history, task history, event tables, or monitoring features, not as the primary purpose of SnowSQL.

Official Snowflake documentation reference:

Snowflake documentation describes SnowSQL as the command-line client for connecting to Snowflake and executing SQL queries, including data loading and unloading commands.

A directory table in Snowflake is an implicit object layered on a stage, whether internal or external. It allows users to query the contents of a stage as if it were a table, providing metadata about the files stored in the stage, such as filenames, file sizes, and last modified timestamps.

Snowflake Documentation: Directory Tables

The correct answer is B. SELECT * FROM table_A TABLESAMPLE (100); .

TABLESAMPLE (100) samples 100 percent of the table, so it returns all rows from table_A.

Why B is correct:

SELECT *

FROM table_A TABLESAMPLE (100);

This requests a 100 percent sample, which is effectively the full table.

Why the other options are incorrect:

A. TABLESAMPLE (0) returns 0 percent of the table, not all rows.

C. SAMPLE (10) returns approximately 10 percent of the rows, not all rows.

D. TABLESAMPLE BERNOULLI (10) samples each row with a 10 percent probability, not all rows.

Official Snowflake documentation reference:

Snowflake documentation explains that SAMPLE / TABLESAMPLE can specify a probability percentage. A value of 100 represents 100 percent of the table.

The correct answer is B. Only one refresh will run at a time .

Failover groups can be refreshed on a schedule to replicate supported account objects and database objects to target accounts. Snowflake does not run overlapping refresh operations for the same failover group.

Why B is correct:

If a scheduled refresh is still running, Snowflake does not start another concurrent refresh for the same failover group. Refresh operations are managed so that only one refresh runs at a time.

Why the other options are incorrect:

A. Multiple refreshes for the same failover group do not run concurrently.

C. Refreshes still require the appropriate privileges and configured replication/failover group permissions.

D. A delayed or long-running refresh does not mean the next refresh is automatically canceled in the way stated. The key behavior is that refreshes do not overlap.

Official Snowflake documentation reference:

Snowflake documentation for replication and failover groups explains that scheduled refreshes are managed by Snowflake and that refresh operations do not run concurrently for the same group.

When querying VARIANT columns (such as JSON), the values are often returned as strings . To convert them to usable SQL types, users must apply the CAST() function (e.g., CAST(column:value AS NUMBER)).

The correct answer is B. Copilot provides assistance when creating and interpreting queries .

Snowflake Copilot is an AI-assisted feature that helps users work with Snowflake more efficiently. It can assist with writing SQL, understanding queries, and interpreting query-related information.

Why B is correct:

Copilot is designed to help users create, refine, and understand SQL queries using natural language assistance.

Why the other options are incorrect:

A. Query optimization is primarily handled by Snowflake’s optimizer and performance features, not Copilot.

C. Copilot does not automatically rewrite table schemas based on inferred data patterns.

D. Copilot is not primarily a feature for executing stored procedures from prompts.

Official Snowflake documentation reference:

Snowflake documentation describes Snowflake Copilot as an AI assistant for helping users generate, understand, and work with SQL and Snowflake data workflows.

To load local files into Snowflake:

First, use the PUT command to upload files from local storage to an internal stage .

Then, use the COPY INTO < table > command to load data from the internal stage into the table.

Details around the privileges that have been granted for all objects in an account. TheACCESS_HISTORYview in Snowflake provides a comprehensive log of access control changes, including grants and revocations of privileges on all securable objects within the account. This information is crucial for auditing and monitoring the security posture of your Snowflake environment.

Here ' s how to understand and use theACCESS_HISTORYview:

Purpose of ACCESS_HISTORY View:It is designed to track changes in access controls, such as when a user or role is granted or revoked privileges on various Snowflake objects. This includes tables, schemas, databases, and more.

Querying ACCESS_HISTORY:To access this view, you can use the following SQL query pattern:

SELECT*FROMSNOWFLAKE.ACCOUNT_USAGE.ACCESS_HISTORYWHEREEVENT_TYPE = ' GRANT ' OREVENT_TYPE = ' REVOKE ' ;

Interpreting the Results:The results from theACCESS_HISTORYview include the object type, the specific privilege granted or revoked, the grantee (who received or lost the privilege), and the timestamp of the event. This data is invaluable for audits and compliance checks.

In Snowflake, shares are used to share data between Snowflake accounts. When creating a share, it is possible to grant access to the share to roles within the Snowflake account that is creating the share. The type of role that can be granted to a share is a Custom role. Custom roles are user-defined roles that account administrators can create to manage access control in a more granular way. Unlike predefined roles such as ACCOUNTADMIN or SYSADMIN, custom roles can be tailored with specific privileges to meet the security and access requirements of different groups within an organization.

Granting a custom role access to a share enables users associated with that role to access the shared data if the share is received by another Snowflake account. It is important to carefully manage the privileges granted to custom roles to ensure that data sharing aligns with organizational policies and data governance standards.

Resource monitors in Snowflake can perform actions such as suspending a virtual warehouse when its credit usage reaches a defined limit and triggering a notification to account administrators when credit usage reaches a specified threshold. These actions help manage and control resource usage and costs within Snowflake.

Snowflake Documentation: Resource Monitors

The correct answer is C. Rotation .

Key-pair authentication uses a public/private key pair to authenticate users or applications. To improve security, keys should be replaced periodically or when there is a possibility that a key has been exposed. This process is called key rotation .

Why C is correct:

Key rotation allows an organization to replace active keys with new keys. In Snowflake, users can have public keys assigned for key-pair authentication, and rotating keys helps maintain secure authentication practices.

Why the other options are incorrect:

A. Authentication is the overall process of verifying identity, not the specific feature for replacing keys.

B. Passkeys are a different authentication mechanism and are not the feature used to replace active key-pair authentication keys.

D. Time-based one-time passcodes are associated with MFA, not key-pair replacement.

Official Snowflake documentation reference:

Snowflake documentation describes key-pair authentication and includes key rotation as a security practice for replacing public/private key pairs.

When using the SAMPLE clause in a query, if the seed is not set, Snowflake will use a different random seed for each execution of the query. This results in different rows being sampled each time, leading to different results. Setting a seed ensures that the same rows are sampled each time the query is run.

Snowflake Documentation: Sampling

A Stream is a Snowflake object that tracks DML changes (INSERTS, UPDATES, DELETES) on a table for CDC (Change Data Capture) use cases.

To use key pair authentication in Snowflake, you need to set the public key for the user. This allows the user to authenticate using their private key.

Generate Key Pair:Generate a public and private key pair.

Set Public Key:

ALTER USER jsmith SET RSA_PUBLIC_KEY= ' MIIBIjANBgkqh... ' ;

Authentication:The user can now authenticate by signing requests with the corresponding private key.