Free Snowflake COF-C02 Practice Exam with Questions & Answers | Set: 3

A directory table in Snowflake is used to store file-level metadata about the data files in a stage. It is conceptually similar to an external table and provides information such as file size, last modified timestamp, and file URL. References: [COF-C02] SnowPro Core Certification Exam Study Guide

 Once an internal stage is dropped in Snowflake, it cannot be recovered or restored using Time Travel or UNDROP commands. The only option is to recreate the dropped stage

In Snowflake, to extract a specific value from a VARIANT column, you use the column name followed by a colon and then the key. The keys are case-sensitive. Therefore, to extract the employee’s name from the “Data” column, the correct syntax is data:employee.name.

 In Snowflake, if a temporary table and a permanent table have the same name within the same schema, the temporary table takes precedence over the permanent table within the session where the temporary table was created4.

When using the ALLOW_CLIENT_MFA_CACHING parameter, a cached Multi-Factor Authentication (MFA) token is valid for up to 4 hours. This allows for continuous, secure connectivity without users needing to respond to an MFA prompt at the start of each connection attempt to Snowflake within this timeframe2.

 A Query Profile provides detailed execution information for a query, which can be used to analyze the performance and behavior of queries. This information can help users optimize and right-size their virtual warehouses for better efficiency. References: [COF-C02] SnowPro Core Certification Exam Study Guide

The Snowflake data types that can be used to build nested hierarchical data are OBJECT and VARIANT. These data types support the storage and querying of semi-structured data, allowing for the creation of complex, nested data structures

 One of the characteristics of materialized views in Snowflake is that they allow multiple tables to be joined in the underlying query. This enables the pre-computation of complex queries involving joins, which can significantly improve the performance of subsequent queries that access the materialized view4. References: [COF-C02] SnowPro Core Certification Exam Study Guide

Views can be used with Secure Data Sharing in Snowflake. Materialized views, external tables, and UDFs are not typically shared directly for security and performance reasons2.

The query acceleration service in Snowflake is designed to benefit queries that involve large scans and selective filters. This service can offload portions of the query processing work to shared compute resources, which can handlethese types of workloads more efficiently by performing morework in parallel and reducing the wall-clock time spent in scanning and filtering2. References: [COF-C02] SnowPro Core Certification Exam Study Guide

Snowflake external tables are read-only, which means data manipulation language (DML) operations like INSERT, RENAME, or ALTER cannot be performed on them. However, external tables can be used for query and join operations3.

 To validate data unloaded using the COPY INTO command, a Snowflakeuser can use the VALIDATION_MODE parameter within the SQL statement to test the files for errors without loading them3.

The purpose of a Query Profile is to provide a detailed analysis of a particular query’s execution plan, including the mechanics, behavior, and performance. It helps in identifying potential performance bottlenecks and areas for optimization