The query acceleration service in Snowflake is beneficial for workloads that include on-demand data analyses. This service optimizes query performance by dynamically allocating additional resources to execute queries faster, particularly useful for ad-hoc analysis where data volume and complexity can vary.
References:
* Snowflake Documentation: Query Acceleration Service

https://docs.snowflake.com/en/sql-reference/functions/validate
The VALIDATE table function accepts a table name and a JOB_ID as input arguments. The JOB_ID can be either a query ID for a COPY INTO <table> command or the keyword _last, which refers to the last load executed during the current session1. The other options are not valid input arguments for the VALIDATE table function.

Micro-partitions in Snowflake are immutable objects, which means once they are written, they cannot be modified. This immutability supports the use of Time Travel, allowing users to access historical data within a defined period. Additionally, micro-partitions can significantly reduce the amount of I/O from object storage to virtual warehouses. This is because Snowflake's query optimizer can skip over micro-partitions that do not contain relevant data for a query, thus reducing the amount of data that needs to be scanned and transferred.
References: [COF-C02] SnowPro Core Certification Exam Study Guide
https://docs.snowflake.com/en/user-guide/tables-clustering-micropartitions.html