SnowPro Core Certification COF-C02 Updated Exam

By default, the ACCOUNTADMIN role in Snowflake has the ability to create a share from a shared database. This role has the highest level of access within a Snowflake account, including the management of all aspects of the account, such as users, roles, warehouses, and databases, as well as the creation and management of shares for secure data sharing with other Snowflake accounts.

References:

Snowflake Documentation: Roles

In Snowflake, semi-structured data is optimally stored using specific data types that are designed to handle the flexibility and complexity of such data. The VARIANT data type can store structured and semi-structured data types, including JSON, Avro, ORC, Parquet, or XML, in a single column. The ARRAY data type, on the other hand, is suitable for storing ordered sequences of elements, which can be particularly useful for semi-structured data types like JSON arrays. These data types provide the necessary flexibility to store and query semi-structured data efficiently in Snowflake.

References:

Snowflake Documentation: Semi-structured Data Types

Query pruning in Snowflake is the mechanism used to limit the number of micro-partitions scanned by a query. By analyzing the filters and conditions applied in a query, Snowflake can skip over micro-partitions that do not contain relevant data, thereby reducing the amount of data processed and improving query performance. This technique is particularly effective for large datasets and is a key component of Snowflake's performance optimization features.

References:

Snowflake Documentation: Query Performance Optimization

For directory tables, a named external stage allows for the automatic refreshing of metadata. This capability is particularly useful when dealing with files stored on external storage services (like Amazon S3, Google Cloud Storage, or Azure Blob Storage) and accessed through Snowflake. The external stage references these files, and the directory table's metadata can be automatically updated to reflect changes in the underlying files.

References:

Snowflake Documentation: External Stages