*DataStage*, an ETL (Extract, Transform, Load) tool developed by IBM, is a powerful platform for data integration tasks. One of the key components in DataStage are the **File Stages**. This article aims to provide a comprehensive understanding of File Stages in DataStage.
File Stages in DataStage are used to read and write files during the ETL process. They can be either Input (source) or Output (target) stages, depending on their role in the job.
**Example of a simple DataStage Job with an Input File Stage (source) and an Output File Stage (target)**
@job
define SIMPLE_FILE_JOB;
@source
define INPUT_FILE_STAGE as file stage;
@sink
define OUTPUT_FILE_STAGE as file stage;
// Job control statements
...
Input File Stages are used to read files during the ETL process. They support various file formats such as CSV, delimited text, fixed format, and more.
**Example of an Input File Stage configuration**
@source
define INPUT_FILE_STAGE as file stage with (
filename => 'input.csv',
directory => '/path/to/input/directory/',
fileAccessMethod => 'readFileIntoMemory',
format => 'CSV',
delimiter => ',',
enclosedBy => '"'
);
Output File Stages are used to write the transformed data into files during the ETL process. They also support various file formats similar to Input File Stages.
**Example of an Output File Stage configuration**
@sink
define OUTPUT_FILE_STAGE as file stage with (
filename => 'output.csv',
directory => '/path/to/output/directory/',
fileAccessMethod => 'writeFile',
format => 'CSV',
delimiter => ',',
enclosedBy => '"'
);
File Stages in DataStage are essential components for handling input and output files during the ETL process. They provide a convenient way to read and write various file formats, making it easier to integrate data from different sources into your DataStage jobs.