Counting in Hadoop Hive

Question

I want to count values similar in a map where key would be the value in the Hive table column and the corresponding value is the count.

For example, for the table below:

+-------+-------+
| Col 1 | Col 2 |
+-------+-------+
| Key1  | Val1  |
| Key1  | Val2  |
| Key2  | Val1  |
+-------+-------+

So the hive query should return something like

Key1=2
Key2=1

Answer 1

It looks like you are looking for a simple group by.

SELECT Col1, COUNT(*) FROM Table GROUP BY Col1