goawk VS qsv

TIL: GoAWK [1] - A POSIX-compliant AWK interpreter written in Go, with CSV support.

[1]: https://github.com/benhoyt/goawk

Another nice project that I have used from time to time (and a very good source for insight) is the awk interpreter written in go https://github.com/benhoyt/goawk

No, I want exactly the opposite - it should be a , b,c as a single string field containing a literal comma, and c. For example, https://github.com/benhoyt/goawk has csv support. https://github.com/benhoyt/goawk/blob/master/docs/csv.md - more info.

I've had a go at solving this in this PR -- feedback welcome. I don't love it, but oh well, it solves the problem at hand. Your comment pointed me in the right direction, thanks again.

There are quite a few re-implementations of scripting languages like Lua in Go. I've written an AWK interpreter in Go.

github.com/benhoyt/goawk -> this library lets you embed an AWK runtime in your applications, very easy to use and useful for enabling some powerful scripting in things you build

Yes, that's right. With my simplistic UTF-8-based implementation it turned length() -- for example -- from O(1) to O(N), turning O(N) algorithms which use length() into O(N^2). See this issue: https://github.com/benhoyt/goawk/issues/93

Similar with substr() and other string functions, which when operating as bytes are O(1), but become O(N) when trying to count the number of codepoints as UTF-8.

GNU Gawk has a fancier approach, which stores strings as UTF-8 as long as it can, but converts to UTF-32 if it needs to (eg: the string is non-ASCII and you call substr).

It looks like Brian Kernighan's code has the same issue with length() and substr(). I'm going to try to email him about this, as I think it's kind of a performance blocker.

I'm not sure if it was via my personal website or just my GitHub profile, but I got my current job at Canonical due to the CTO there reaching out about my GoAWK project (https://github.com/benhoyt/goawk). I get regular recruitment emails because I have my CV/resume online: most of them are very low-effort, but 1 in 20 or something are interesting emails where the recruiter has actually looked at my website and will tailor it personally. I also just enjoy technical writing, and get joy out of sharing it on HN. So it's "worth it" for me.

Thanks for the detailed feedback @snidane!

As maintainer of qsv, here's my reply:

- Given qsv's rapid release cycle (173 releases over three years), the auto-update check is essential at the moment. Once we reach 1.0, I'll turn it off. For now, given your feedback, I've only made it check 10% of the time.

- Pivot is in the backlog and I'll be sure to add unpivot when I implement it. (https://github.com/jqnatividad/qsv/issues/799)

- I'll add a dedicated summing command with the group by (-by) and window by (-over) capability (https://github.com/jqnatividad/qsv/issues/1514). Do note that `stats` has basic sum as @ezequiel-garzon pointed out.

- With the `enum` command, qsv can achieve what you proposed with `laminate`. E.g. qsv enum --new-column newcol --constant newconstant mydata.csv --output laminated-data.csv

- With the cat rowskey command, qsv can already concatenate files with mismatched headers.

- other file formats. qsv supports parquet, csv, tsv, excel, ods, datapackage, sqlite and more (see https://github.com/jqnatividad/qsv/tree/master#file-formats). Fixed-format though is not supported yet and quite interesting, and have added it to the backlog (https://github.com/jqnatividad/qsv/issues/1515)

- as to "enable embedding outputs of commands", qsv is composable by design, so you can use standard stdin/stdout redirection/piping techniques to have it work with other CLI tools like jq, awk, etc.

Finally, just released v0.120.0 that already incorporates the less aggressive self-update check. https://github.com/jqnatividad/qsv/releases/tag/0.120.0

qsv [1] also has a sqlp command which lets you run Polars SQL queries (even on multiple files). Here I'll send the csv data from stdin (represented by -) and then (optionally) pipe the output to the table command for formatting. The shape of the result is also printed to stderr (the (4, 2) below).

[1] https://github.com/jqnatividad/qsv

$ echo 'Name,Department,Salary

It works quite well IMHO. Using the mlua crate, I’ve managed to integrate Luau as a very powerful data-wrangling DSL for qsv (https://github.com/jqnatividad/qsv)

Maybe this might be better done using this? https://github.com/jqnatividad/qsv

https://github.com/jqnatividad/qsv is another option.