Why Hive enables SQL on Hadoop - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a Hive table named 'employees'.

Hadoop

CREATE TABLE employees (id INT, name STRING) [1];

Drag options to blanks, or click blank then click option'

ASTORED AS TEXTFILE

BSELECT * FROM employees

CINSERT INTO employees

DDROP TABLE employees

Attempts:

3 left

💡 Hint

Common Mistakes

Using SELECT or INSERT statements instead of storage format.

Omitting the storage format clause.

The STORED AS TEXTFILE clause defines the file format for the Hive table, which is necessary when creating tables.

2fill in blank

medium

Complete the code to query all records from the 'employees' table.

Hadoop

SELECT [1] FROM employees;

Drag options to blanks, or click blank then click option'

Aname

Bid

CCOUNT(*)

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Selecting only one column when all are needed.

Using aggregate functions without GROUP BY.

The * symbol selects all columns from the table.

3fill in blank

hard

Fix the error in the Hive query to count employees.

Hadoop

SELECT COUNT([1]) FROM employees;

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Aid

B*

Cname

Demployees

Attempts:

3 left

💡 Hint

Common Mistakes

Using table name inside COUNT instead of * or column.

Using a column that may have NULL values.

Using COUNT(*) counts all rows in the table.

4fill in blank

hard

Fill both blanks to create a Hive query that filters employees with id greater than 100.

Hadoop

SELECT * FROM employees WHERE id [1] [2];

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A>

B100

C<

D50

Attempts:

3 left

💡 Hint

Common Mistakes

Using less than operator instead of greater than.

Using wrong number for filtering.

The query filters rows where id > 100.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps employee names to their ids if id is less than 200.

Hadoop

{ [3].[1]: [3].[2] for [3] in employees if [3].id < 200 }

Drag options to blanks, or click blank then click option'

Aname

Bid

Cemployee

Demp

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names in comprehension.

Mixing keys and values in the dictionary.

This comprehension creates a dictionary with employee names as keys and ids as values for employees with id less than 200.