Fail-safe is a feature in Snowflake that provides an additional layer of data protection. After the Time Travel retention period ends, Fail-safe offers a non-configurable 7-day period during which historical data may be recoverable by Snowflake. This period is designed to protect against accidental data loss and is not intended for customer access.

Clustering in Snowflake refers to the organization of data within micro-partitions, which are contiguous units of storage within Snowflake tables. Clustering keys can be defined to co-locate similar rows in the same micro-partitions, improving scan efficiency and query performance12.

In Snowflake, the authorization to execute CREATE <object> statements, such as creating tables, views, databases, etc., is determined by the role currently set as the user's primary role. The primary role of a user or session specifies the set of privileges (including creation privileges) that the user has. While users can have multiple roles, only the primary role is used to determine what objects the user can create unless explicitly specified in the session.

Snowflake allows users to write custom application logic in JavaScript for two types of objects: Stored Procedures and User-Defined Functions (UDFs).
Stored Procedures: Snowflake stored procedures can be written in JavaScript to encapsulate complex business logic and procedural operations.
CREATE OR REPLACE PROCEDURE my_procedure()
RETURNS STRING
LANGUAGE JAVASCRIPT
EXECUTE AS CALLER
AS
$$
// JavaScript logic here
$$;
User-Defined Functions (UDFs): Snowflake UDFs can be written in JavaScript to perform custom calculations or operations on data.
CREATE OR REPLACE FUNCTION my_function(x FLOAT)
RETURNS FLOAT
LANGUAGE JAVASCRIPT
AS
$$
return x * 2;
$$;
Reference:
Snowflake Documentation: Stored Procedures
Snowflake Documentation: User-Defined Functions (UDFs)

Snowflake bills virtual warehouse usage in one-minute increments, rounding up to the nearest minute for any partial minute of compute time used. If a virtual warehouse runs for 61 seconds and then, after being shut down, restarts and runs for an additional 30 seconds, the total time billed would be 120 seconds or 2 minutes. The first 61 seconds are rounded up to 2 minutes, and the subsequent 30 seconds are within a new minute, which is also rounded up to the nearest minute.
Reference:
Snowflake Documentation: Virtual Warehouses Billing