From 4e0b943a25ca68d7743c8661c0c0ae75f6bd4d81 Mon Sep 17 00:00:00 2001 From: Joel Natividad <1980690+jqnatividad@users.noreply.github.com> Date: Sun, 7 Jan 2024 09:09:06 -0500 Subject: [PATCH] `readme`: `reverse` now has index support and can work in streaming mode --- README.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/README.md b/README.md index b0f3e1a08..9457145dc 100644 --- a/README.md +++ b/README.md @@ -62,7 +62,7 @@ | [py](/src/cmd/python.rs#L2)
✨🔣 | Create a new computed column or filter rows by evaluating a python expression on every row of a CSV file. Python's [f-strings](https://www.freecodecamp.org/news/python-f-strings-tutorial-how-to-use-f-strings-for-string-formatting/) is particularly useful for extended formatting, [with the ability to evaluate Python expressions as well](https://github.com/jqnatividad/qsv/blob/4cd00dca88addf0d287247fa27d40563b6d46985/src/cmd/python.rs#L23-L31). | | [rename](/src/cmd/rename.rs#L2) | Rename the columns of a CSV efficiently. | | [replace](/src/cmd/replace.rs#L2) | Replace CSV data using a regex. Applies the regex to each field individually. | -| [reverse](/src/cmd/reverse.rs#L2)
🤯 | Reverse order of rows in a CSV. Unlike the `sort --reverse` command, it preserves the order of rows with the same key. | +| [reverse](/src/cmd/reverse.rs#L2)
📇🤯 | Reverse order of rows in a CSV. Unlike the `sort --reverse` command, it preserves the order of rows with the same key. If an index is present, it works with constant memory. Otherwise, it will load all the data into memory. | | [safenames](/src/cmd/safenames.rs#L2)
![CKAN](docs/images/ckan.png) | Modify headers of a CSV to only have ["safe" names](/src/cmd/safenames.rs#L5-L14) - guaranteed "database-ready"/"CKAN-ready" names. | | [sample](/src/cmd/sample.rs#L2)
📇🌐🏎️ | Randomly draw rows (with optional seed) from a CSV using [reservoir sampling](https://en.wikipedia.org/wiki/Reservoir_sampling), using memory proportional to the sample size. If an index is present, using random indexing with constant memory. | | [schema](/src/cmd/schema.rs#L2)
📇😣🏎️ | Infer schema from CSV data, replete with data type & domain/range validation & output in [JSON Schema](https://json-schema.org/) format. Uses multithreading to go faster if an index is present. See `validate` command to use the generated JSON Schema to validate if similar CSVs comply with the schema. |