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CSV (Comma-Separated Value) Reader/Writer

FME reads and writes files in CSV format.


Comma-Separated Value, or CSV, is a way to store structured information in an ASCII file format, making it a very simple database. CSV is a popular format for exchanging information between spreadsheets, databases, and other software applications.

In FME, CSV is treated as a database format. Each line in the file is a record, with a comma (or other) character between each field within the record.

There is often a header line to provide names for the fields. For example:

company, address, telephone, web

Safe Software Inc, 132nd Street Surrey BC, 604-501-9985,

Files do not have to be comma-separated: FME can recognize any file with any separator or delimiter character, as long as you specify that character in the parameter settings.

CSV File Extensions

By convention, CSV files use the .csv extension, but the reader and writer can use any extension.

The CSV reader can read from a gzipped file with the extension .csv.gz, and the CSV writer can write a gzipped file if the extension of the destination file ends with .gz.

Reader Overview

The CSV reader produces an FME feature for each line in each of the CSV files inside the given folder. The CSV reader first scans the folder for all CSV files that are defined in the workspace.

If IDs lines are specified, the CSV reader processes only the specified files; otherwise, it reads all files in the folder. Optionally, a single CSV file can be given in the workspace. In this case, only that CSV file is read.

The CSV reader can also read data consisting of fixed-width columns without a separator, if the character spacing the data (usually a space character) does not appear in the data itself. Use the parameter Skip Duplicate Delimiters. (An alternative method is to use the Text File Reader/Writer and AttributeSplitter transformer.)

Writer Overview

The CSV writer writes all attributes of a feature to an CSV file. Features of different types are written to different CSV files.

To view non-spatial data in the Data Inspector application, select Tools > Select All Features with No Geometry.

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