index

Create an index for a CSV. This is very quick (even the 15gb, 28m row NYC 311 dataset takes all of 14 seconds to index) & provides constant time indexing/random access into the CSV. With an index, count, sample & slice work instantaneously; random access mode is enabled in luau; and multithreading is enabled for the frequency, split, stats & schema commands.

Table of Contents | Source: src/cmd/index.rs

Description | Usage | Index Options | Common Options

Description ↩

Creates an index of the given CSV data, which can make other operations like slicing, splitting and gathering statistics much faster.

Note that this does not accept CSV data on stdin. You must give a file path. The index is created at 'path/to/input.csv.idx'. The index will be automatically used by commands that can benefit from it. If the original CSV data changes after the index is made, commands that try to use it will result in an error (you have to regenerate the index before it can be used again).

However, if the environment variable QSV_AUTOINDEX_SIZE is set, qsv will automatically create an index when the input file size >= specified size (bytes). It will also automatically update stale indices as well.

See also https://github.com/dathere/qsv/wiki/Indexing-Compression-Diff#index

Usage ↩

qsv index [options] <input>
qsv index --help

Index Options ↩

Option	Type	Description	Default
‑o, ‑‑output	string	Write index to instead of .idx. Generally, this is not currently useful because the only way to use an index is if it is specially named .idx.

Common Options ↩

Option	Type	Description	Default
‑h, ‑‑help	flag	Display this message

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Source: src/cmd/index.rs | Table of Contents | README