WRwrycoder·Apr 5, 2022
I found this license for jd itself. It is free only for non-commercial use:
https://github.com/jsoftware/data_jd/blob/master/doc/License...
The link you mentioned only applies to the jsource folder: the jengine code.
In Jdjsoftware
data_jd
J2022–2022
jsoftware / data_jd
data_jd
Jd
5Distinct people
5Mentions
0Explicit recommenders
14GitHub stars
What to know before exploring
What it is
Jd
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
No recommendation phrase was found in the indexed comments.
No classified warning is attached to this page. Read the discussions before treating silence as approval.
Also in these discussions
No other repository is repeatedly linked in the same discussions.
This week on Hacker News
Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 2:17:07 AM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by week5 dated mentions
Observed mentions: 2022-04-04 12:44:35 UTC to 2022-10-17 02:32:17 UTC. Weeks start Monday, UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| Apr 4 | 2022-04-04 00:00:00 UTC | 2022-04-11 00:00:00 UTC | 4 | 0 | 4 |
| Apr 11 | 2022-04-11 00:00:00 UTC | 2022-04-18 00:00:00 UTC | 0 | 0 | 0 |
| Apr 18 | 2022-04-18 00:00:00 UTC | 2022-04-25 00:00:00 UTC | 0 | 0 | 0 |
| Apr 25 | 2022-04-25 00:00:00 UTC | 2022-05-02 00:00:00 UTC | 0 | 0 | 0 |
| May 2 | 2022-05-02 00:00:00 UTC | 2022-05-09 00:00:00 UTC | 0 | 0 | 0 |
| May 9 | 2022-05-09 00:00:00 UTC | 2022-05-16 00:00:00 UTC | 0 | 0 | 0 |
| May 16 | 2022-05-16 00:00:00 UTC | 2022-05-23 00:00:00 UTC | 0 | 0 | 0 |
| May 23 | 2022-05-23 00:00:00 UTC | 2022-05-30 00:00:00 UTC | 0 | 0 | 0 |
| May 30 | 2022-05-30 00:00:00 UTC | 2022-06-06 00:00:00 UTC | 0 | 0 | 0 |
| Jun 6 | 2022-06-06 00:00:00 UTC | 2022-06-13 00:00:00 UTC | 0 | 0 | 0 |
| Jun 13 | 2022-06-13 00:00:00 UTC | 2022-06-20 00:00:00 UTC | 0 | 0 | 0 |
| Jun 20 | 2022-06-20 00:00:00 UTC | 2022-06-27 00:00:00 UTC | 0 | 0 | 0 |
| Jun 27 | 2022-06-27 00:00:00 UTC | 2022-07-04 00:00:00 UTC | 0 | 0 | 0 |
| Jul 4 | 2022-07-04 00:00:00 UTC | 2022-07-11 00:00:00 UTC | 0 | 0 | 0 |
| Jul 11 | 2022-07-11 00:00:00 UTC | 2022-07-18 00:00:00 UTC | 0 | 0 | 0 |
| Jul 18 | 2022-07-18 00:00:00 UTC | 2022-07-25 00:00:00 UTC | 0 | 0 | 0 |
| Jul 25 | 2022-07-25 00:00:00 UTC | 2022-08-01 00:00:00 UTC | 0 | 0 | 0 |
| Aug 1 | 2022-08-01 00:00:00 UTC | 2022-08-08 00:00:00 UTC | 0 | 0 | 0 |
| Aug 8 | 2022-08-08 00:00:00 UTC | 2022-08-15 00:00:00 UTC | 0 | 0 | 0 |
| Aug 15 | 2022-08-15 00:00:00 UTC | 2022-08-22 00:00:00 UTC | 0 | 0 | 0 |
| Aug 22 | 2022-08-22 00:00:00 UTC | 2022-08-29 00:00:00 UTC | 0 | 0 | 0 |
| Aug 29 | 2022-08-29 00:00:00 UTC | 2022-09-05 00:00:00 UTC | 0 | 0 | 0 |
| Sep 5 | 2022-09-05 00:00:00 UTC | 2022-09-12 00:00:00 UTC | 0 | 0 | 0 |
| Sep 12 | 2022-09-12 00:00:00 UTC | 2022-09-19 00:00:00 UTC | 0 | 0 | 0 |
| Sep 19 | 2022-09-19 00:00:00 UTC | 2022-09-26 00:00:00 UTC | 0 | 0 | 0 |
| Sep 26 | 2022-09-26 00:00:00 UTC | 2022-10-03 00:00:00 UTC | 0 | 0 | 0 |
| Oct 3 | 2022-10-03 00:00:00 UTC | 2022-10-10 00:00:00 UTC | 0 | 0 | 0 |
| Oct 10 | 2022-10-10 00:00:00 UTC | 2022-10-17 00:00:00 UTC | 0 | 0 | 0 |
| Oct 17 | 2022-10-17 00:00:00 UTC | 2022-10-24 00:00:00 UTC | 1 | 0 | 1 |
What Hacker News says
4 sourcesHere's one of the more central files that ties into how a Jd database is laid out:
https://github.com/jsoftware/data_jd/blob/master/base/common...
Not that I claim anyone in particular can read it of course. Jd uses a hierarchy of folder, database, table, column that's handled with an object system to share code between them. A folder is just a place to put databases and hardly needs to add anything, while the other levels have a lot of extra functionality. As an inverted database, Jd stores each column in a file, and accesses it using memory mapping.
https://github.com/jsoftware/data_jd/blob/master/base/folder...
https://github.com/jsoftware/data_jd/blob/master/base/table....
(I designed this system when I did some of the early work to turn JDB into Jd as a summer intern)
In JdJ is fully opensource: https://github.com/jsoftware/jsource
Most of jd's source is publicly available: https://github.com/jsoftware/data_jd
In JdAn example J file because this link doesn't say much:
https://github.com/jsoftware/data_jd/blob/master/csv/csv.ijs
In Jd