How do you view the execution plan in Hive?

In Hive, you can use the ‘EXPLAIN’ command to view the execution plan. The execution plan describes each step of the Hive query and their relationships. Follow these steps to view the Hive execution plan: 1. Open the Hive Shell and connect to the Hive server. 2. Enter the query that needs to be explained, for example:

EXPLAIN SELECT * FROM tablename;

After executing the `EXPLAIN` command, Hive will generate the query execution plan and display it on the screen. The execution plan is usually displayed in a tree-like structure, where each node represents an operation in the query. Each node contains detailed information about that operation, such as the operators used, the required inputs and outputs, etc. You can use the following command options to further customize the display of the execution plan: – `EXTENDED`: Display more detailed information about the execution plan. – `FORMAT`: Specify the output format, for example `FORMAT JSON`. – `DEPENDENCY`: Display the dependencies of the query. For example, the following command will display an extended JSON format execution plan:

EXPLAIN EXTENDED FORMAT JSON SELECT * FROM tablename;

This can provide a more detailed understanding of how the query is executed, helping to optimize query performance and understand the query execution process.