This small tool spawn off from our need during the Nigeria MDGs Info System data mopup process, we needed to process millions of lines of csv file with a constraint of memory, and a good way to go was to split the csv based on one column and have each be processed separately in R.
We used streams to pick up one line at a time and dump the result to the output directory.
To use, do
csv-split -i [file_name] -b [group_by_column] [-o [output_directory]]
if output_directory is not specified, it will default to [file_name]_by_[group]
you can also pipe from stdin:
cat data.csv | csv-split -b [group_by_column]
Usage: csv-split [options]
Options:
-h, --help output usage information
-V, --version output the version number
-i, --input <file> select an input csv
-o, --output <directory> select an output directory
-b, --groupby <group> the column you want to group by