In this chapter, you learned to use
SELECT statements to discover the data you need. Then, we introduced Hive operations to link different datasets from vertical or horizontal directions using
UNION ALL. After going through this chapter, we should be able to use the
SELECT statement with different
DISTINCT, and complex subqueries. We should be able to understand and use different types of
JOIN statements to link the different datasets horizontally and
UNION ALL to combine the different datasets vertically.
In the next chapter, we will talk about the details of exchange, order, and transforming data as well as transactions in Hive.