COF-C02 Exam Dumps - Snowflake SnowPro Core Certification Questions and Answers

 In a multi-cluster warehouse with an economy scaling policy, queries will wait in the queue for 2 minutes before another cluster is started. This is to minimize costs by allowing queries to queue up for a short period before adding additional compute resources. References: [COF-C02] SnowPro Core Certification Exam Study Guide

 Scaling up the virtual warehouse in Snowflake involves increasing the compute resources available for a single warehouse, which can improve the performance of large and complex queries by providing more CPU and memory resources. References: Based on general cloud data warehousing knowledge as of 2021.

Pre-signed URLs in Snowflake allow users to access unstructured data without the need for authentication into Snowflake or passing an authorization token. These URLs are open and can be directly accessed or downloaded by any user or application, making them ideal for business intelligence applications or reporting tools that need to display unstructured file contents

 In Snowflake, a User-Defined Table Function (UDTF) can be accessed in the FROM clause of a query. UDTFs return a set of rows with one or more columns, which can be queried like a regular table

 In the Activity section in Snowsight, Snowflake users can explore the performance of executed queries. This includes monitoring queries, viewing details about queries, including performance data, and exploring each step of an executed query in the query profile1.

 Snowflake’s column level security features include Dynamic Data Masking and External Tokenization. Dynamic Data Masking uses masking policies to selectively mask data at query time, while External Tokenization allows for the tokenization of data before loading it into Snowflake and detokenizing it at query runtime5.

 Network policies in Snowflake can be applied to users and accounts. These policies control inbound access to the Snowflake service and internal stages, allowing or denying access based on the originating network identifiers12.

References: [COF-C02] SnowPro Core Certification Exam Study Guide

The Snowflake PUT command is used to upload files from a local file system to Snowflake stages, specifically the user stage, table stage, and internal named stage. These stages are where the data files are temporarily stored before being loaded into Snowflake tables

 SnowCD (Snowflake Connectivity Diagnostic Tool) is the best tool provided by Snowflake for troubleshooting network connectivity issues. It helps diagnose and resolve issues related to connecting to Snowflake services

https://docs.snowflake.com/en/user-guide/snowcd.html#:~:text=SnowCD%20(i.e.%20Snowflake%20Connectivity%20Diagnostic,their%20network%20connection%20to%20Snowflake .

To optimize query performance in Snowflake, users can cluster a table, which organizes the data in a way that minimizes the amount of data scanned during queries. Additionally, enabling the search optimization service can improve the performance of selective point lookup queries on large tables34.

 Snowflake maintains a result cache that stores the results of every query for 24 hours. If the same query is executed again within this time frame and the data has not changed, Snowflake will retrieve the data from the result cache instead of using a virtual warehouse to recompute the results2.

In Snowflake, a tabular User-Defined Function (UDF) is defined with a return clause that includes the keyword “TABLE.” This indicates that the UDF will return a set of rows, which can be used in the FROM clause of a query. References: Based on my internal knowledge as of 2021.

 When unloading data, Snowflake assigns each file a unique name to ensure there is no overlap or confusion between files. This is part of the bulk unloading process where data is exported from Snowflake tables into flat files3.

To find out which numeric values are present in both tables, the INTERSECT set operator should be used. This operator returns rows from one query’s result set which also appear in another query’s result set, effectively finding the common elements between the two tables45.

Clones in Snowflake have the advantage of being created almost instantly and saving space by not duplicating storage. This is due to Snowflake’s zero-copy cloning feature, which allows for the creation of object clones without the additional storage costs typically associated with data duplication23. Clones are independent of the original table and do not stay in sync with it, nor do they inherently have better query performance. However, they do inherit the time travel history from the original table at the time of cloning