Sqoop Interview Questions and Answers

Ques 1. What is Sqoop?

Sqoop is a tool designed for efficiently transferring bulk data between Apache Hadoop and structured datastores such as relational databases.

Ques 2. What is the purpose of the --target-dir option in Sqoop import?

The --target-dir option specifies the HDFS directory where the imported data will be stored.

Ques 3. What is the purpose of the --warehouse-dir option in Sqoop?

The --warehouse-dir option specifies the base directory in HDFS where imported data is stored.

Ques 4. What is the purpose of the --update-key option in Sqoop export?

The --update-key option specifies the column(s) used to identify rows for updates when performing an export.

Ques 5. Explain the purpose of the --as-textfile option in Sqoop.

The --as-textfile option in Sqoop specifies that the data should be stored in text format in HDFS during import.

Ques 6. How can you perform a full load import in Sqoop?

A full load import in Sqoop can be done by using the --m (or --num-mappers) option with a value of 1 to import the data using a single mapper.

Example:

sqoop import --connect jdbc:mysql://localhost:3306/db --table mytable --m 1

Ques 7. What is the purpose of the --null-string and --null-non-string options in Sqoop?

These options are used to specify the representation of NULL values in the imported data for string and non-string columns, respectively.

Example:

sqoop import --connect jdbc:mysql://localhost:3306/db --table mytable --null-string --null-non-string -1

Ques 8. What is the purpose of the --columns option in Sqoop?

The --columns option allows you to specify a comma-separated list of columns to import, excluding others from the source table.

Example:

sqoop import --connect jdbc:mysql://localhost:3306/db --table mytable --columns id,name

Ques 9. What is the purpose of the --fetch-size option in Sqoop?

The --fetch-size option specifies the number of rows to fetch in each round trip between Sqoop and the database during import.

Example:

sqoop import --connect jdbc:mysql://localhost:3306/db --table mytable --fetch-size 100