The functions and roles of components such as Metastore, Driver, and Executor in Hive.

1. The Hive Metastore is an essential component in Hive, used to store metadata information such as databases, tables, partitions, columns, table storage formats, delimiters, etc. It is typically used in conjunction with relational databases like MySQL or PostgreSQL to ensure the persistence of metadata and data.
2. The Hive Driver serves as the central control point for Hive queries, responsible for parsing user-submitted HiveQL query statements, generating logical query plans, and converting them into physical execution plans. The Driver also interacts with the Metastore to retrieve metadata information for query execution. Lastly, the Driver is responsible for submitting the physical execution plan to the Executor for actual query execution.
3. Hive Executor is the execution engine for Hive queries, responsible for executing the physical execution plan generated by the Driver. The Executor mainly consists of two components: TaskTracker and Task. TaskTracker distributes tasks to available computing nodes for execution, while Task is responsible for carrying out specific tasks such as scanning data and calculations. The Executor also returns the execution results to the Driver.

In general, Metastore is responsible for storing metadata information, Driver is responsible for generating query plans and scheduling tasks, and Executor is responsible for executing queries. These three components work together to achieve the functionality of Hive queries.