tricks.rst

Tips and Tricks

Reading compressed CSVs

csvkit has builtin support for reading gzip or bz2 compressed input files. This is automatically detected based on the file extension. For example:

$ csvstat examples/dummy.csv.gz
$ csvstat examples/dummy.csv.bz2

Please note, the files are decompressed in memory, so this is a convenience, not an optimization.

Specifying STDIN as a file

Most tools default to STDIN if no filename is specified, but tools like scripts/csvjoin and scripts/csvstack accept multiple files, so this is not possible. To work around this it is also possible to specify STDIN by using - as a filename. For example, these three commands are functionally identical:

$ csvstat examples/dummy.csv
$ cat examples/dummy.csv | csvstat
$ cat examples/dummy.csv | csvstat -

This specification allows you to, for instance, csvstack input on STDIN with another file:

$ cat ~/src/csvkit/examples/dummy.csv | csvstack ~/src/csvkit/examples/dummy3.csv -