Hadoop Essentials

Imports

Sqoop import is executed in two steps:

1. Gather metadata
2. Submit map only job

The following figure explains the import in to Sqoop:

Sqoop import provides the following options:

• Import an entire table:

  sqoop import \
  --connect jdbc:mysql://mysql.example.com/sqoop \
  --username sqoop \
  --password sqoop \
  --table cities

• Import a subset of data:

  sqoop import \
  --connect jdbc:mysql://mysql.example.com/sqoop \
  --username sqoop \
  --password sqoop \
  --table cities \
  --where "country = 'USA'"

• Change file format, by default the data will be saved in tab separated csv format but Sqoop provides option for saving the data in Hadoop SequenceFile, Avro binary format ...