Bucketing for sampling in Hadoop - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a bucketed table with 4 buckets.

Hadoop

CREATE TABLE user_data_bucketed (user_id INT, name STRING) CLUSTERED BY (user_id) INTO [1] BUCKETS STORED AS ORC;

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

A4

B2

C6

D8

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong number of buckets that doesn't match the sampling requirement.

Forgetting to specify the CLUSTERED BY column.

The code creates a bucketed table with 4 buckets using the CLUSTERED BY clause.

2fill in blank

medium

Complete the code to sample 25% of data from a bucketed table.

Hadoop

SELECT * FROM user_data_bucketed TABLESAMPLE(BUCKET [1] OUT OF 4 ON user_id);

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

A2

B4

C3

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using bucket number 0 which is invalid.

Using bucket number equal to total buckets which returns all data.

Sampling bucket 1 out of 4 buckets gives approximately 25% of the data.

3fill in blank

hard

Fix the error in the bucketing clause to correctly bucket by user_id.

Hadoop

CREATE TABLE user_logs (user_id INT, action STRING) CLUSTERED BY ([1]) INTO 8 BUCKETS STORED AS PARQUET;

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

Auser

Buser_id

Cuserid

Did

Attempts:

3 left

💡 Hint

Common Mistakes

Using a column name that does not exist in the table.

Misspelling the column name.

The column name is user_id, so it must be used exactly in the CLUSTERED BY clause.

4fill in blank

hard

Fill both blanks to create a bucketed table and sample bucket 3 out of 5.

Hadoop

CREATE TABLE sales_data (sale_id INT, amount FLOAT) CLUSTERED BY ([1]) INTO [2] BUCKETS STORED AS TEXTFILE;
SELECT * FROM sales_data TABLESAMPLE(BUCKET 3 OUT OF 5 ON sale_id);

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

Asale_id

Bamount

C5

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Mismatching bucket count between table and sampling.

Using wrong column for bucketing.

The table is bucketed by sale_id into 5 buckets to match the sampling of bucket 3 out of 5.

5fill in blank

hard

Fill all three blanks to create a bucketed table, insert data, and sample bucket 2 out of 4.

Hadoop

CREATE TABLE employee_data (emp_id INT, name STRING) CLUSTERED BY ([1]) INTO [2] BUCKETS STORED AS ORC;
INSERT INTO employee_data VALUES (1, 'Alice'), (2, 'Bob');
SELECT * FROM employee_data TABLESAMPLE(BUCKET [3] OUT OF 4 ON emp_id);

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

Aemp_id

B4

C2

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong column for bucketing.

Mismatching bucket count and sampling bucket number.

The table is bucketed by emp_id into 4 buckets, and sampling bucket 2 out of 4 selects 50% of data.