hive array

Hive supports arrays as a data type. An array in Hive is an ordered collection of elements of the same type. You can declare an array column in a table, or use arrays in Hive queries to perform operations like filtering, aggregating, and joining data.

To declare an array column in a Hive table, you can use the ARRAY keyword in the column definition. For example:

CREATE TABLE my_table (
  id INT,
  names ARRAY<STRING>
);

In the above example, the `names` column is defined as an array of strings.

You can also use arrays in Hive queries to perform various operations. For instance, you can select specific elements from an array, filter rows based on array values, explode arrays to create additional rows, aggregate array values, and so on.

Here's an example of querying an array column:

SELECT id, names[0] FROM my_table;

In the above query, we are selecting the first element of the `names` array for each row.

Hive provides a set of built-in functions specifically designed for working with arrays. These functions include `array_contains`, `explode`, `posexplode`, `size`, `sort_array`, and more.

I hope this provides a good overview of using arrays in Hive. Let me know if you have any more questions!