Generate and view Apache Hive statistics

You can use statistics to optimize queries for improved performance. The cost-based optimizer (CBO) also uses statistics to compare query plans and choose the best one. By viewing statistics instead of running a query, you can often get answers to your data questions faster.

This task shows how to generate different types of statistics about a table.

Launch a Hive shell and log in.
Gather table statistics for the non-partitioned table mytable:
```
ANALYZE TABLE mytable COMPUTE STATISTICS;
```
View table statistics you generated:
```
DESCRIBE EXTENDED mytable;
```

Gather column-level statistics for the table:

ANALYZE TABLE mytable COMPUTE STATISTICS FOR COLUMNS;

View column statistics for the col_name column in my_table in the my_db database:
```
DESCRIBE FORMATTED my_db.my_table col_name;
```