“ffe” is a command-line tool used to extract specific fields from a flat database file and write them to another format. It operates based on a configuration file that interprets the input data and formats the output accordingly. With “ffe,” users can extract relevant information from structured data and convert it into a more usable or compatible format.
Here are the key features and functionalities of “ffe”:
- Flat Database Extraction: “ffe” is designed to work with flat database files, which are typically structured as rows and columns. These files can include formats such as CSV (Comma-Separated Values) or TSV (Tab-Separated Values). “ffe” allows users to extract specific fields or columns from these files based on their configuration requirements.
- Field Extraction: With the help of a configuration file, “ffe” enables users to define the fields they want to extract from the input database file. The configuration file specifies the names or indices of the desired fields and provides instructions on how to interpret and process the data.
- Output Formatting: “ffe” supports writing the extracted fields to another file or output stream in a specified format. The output can be formatted as plain text or structured data formats such as JSON (JavaScript Object Notation) or XML (eXtensible Markup Language). The configuration file guides the transformation process, allowing users to customize the output format according to their needs.
- Flexibility through Configuration: The configuration file plays a crucial role in “ffe” as it determines how the input data is interpreted and how the extracted fields are formatted in the output. It allows users to specify field names or indices, define delimiters or separators, handle data types, and apply transformations or formatting rules to the extracted fields.
- Automation and Scripting: “ffe” is suitable for automation and scripting tasks. Users can integrate “ffe” into their workflows or scripts, utilizing its field extraction capabilities to process large datasets, automate data extraction, or transform data into a different format programmatically.
- Command-Line Interface (CLI): “ffe” is primarily a command-line tool, offering a straightforward interface for executing the field extraction process. Users provide the input database file, specify the configuration file, and define the output format and destination.
ffe Command Examples
1. Display all input data using the specified data configuration:
# ffe --configuration=/path/to/config.ffe /path/to/input
2. Convert an input file to an output file in a new format:
# ffe --output=/path/to/output -c /path/to/config.ffe /path/to/input
3. Select input structure and print format from definitions in ~/.fferc config file:
# ffe --structure=structure --print=format /path/to/input
4. Write only the selected fields:
# ffe --field-list="FirstName,LastName,Age" -c /path/to/config.ffe /path/to/input
5. Write only the records that match an expression:
# ffe -e "LastName=Smith" -c /path/to/config.ffe /path/to/input
6. Display help:
# ffe --help
Summary
Overall, “ffe” is a versatile tool for extracting fields from flat database files and transforming them into a desired output format. By leveraging a configuration file, users can tailor the extraction process to their specific needs, interpret the input data correctly, and format the extracted fields in a way that is compatible with other tools or systems. Whether it’s extracting specific columns from CSV files or transforming structured data into a more usable format, “ffe” provides flexibility and automation capabilities for efficient data extraction and transformation tasks.