Snowflake recommends using columns with very high cardinality and those that are most actively used in selective filters as clustering keys. High cardinality columns have a wide range of unique values, which helps in evenly distributing the data across micro-partitions. Columns used in selective filters help in pruning the number of micro-partitions to scan, thus improving query performance.

Reference: Based on general database optimization principles.

The Snowflake Cloud Services layer coordinates activities within the Snowflake account. It is responsible for tasks such as authentication, infrastructure management, metadata management, query parsing and optimization, and access control.

Reference: Based on general cloud database architecture knowledge.

Snowflake recommends creating objects with a role that has the necessary privileges and is not overly permissive. SYSADMIN is typically used for managing system-level objects and operations. Creating objects with a custom role and granting this role to SYSADMIN allows for more granular control and adherence to the principle of least privilege.

Reference: Based on best practices for database object ownership and role management.

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.

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

To access a JSON object in Snowflake, dot notation is used where the path to the object is specified after the column name containing the JSON data. Both lowercase and uppercase can be used for attribute names, so both ''name'' and ''Name'' are valid.

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

When a database is cloned in Snowflake, it does not retain any privileges that were granted on the source object. The clone will need to have privileges reassigned as necessary for users to access it.

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

Snowflake supports semi-structured data types, which include OBJECT and VARIANT. These data types are capable of storing JSON-like data structures, allowing for flexibility in data representation.OBJECT can directly contain VARIANT, and thus indirectly contain any other data type, including itself1.

Snowflake's hierarchical key model includes several levels of keys, where Account master keys and File keys are part of this hierarchy.Account master keys are used to encrypt all the data within an account, while File keys are used to encrypt individual files within the database2.

Snowflake recommends using the COPY command for bulk loading data batches from files already available in cloud storage.This command allows for efficient and large-scale data loading operations from files staged in cloud storage into Snowflake tables3.