html_url,issue_url,id,node_id,user,user_label,created_at,updated_at,author_association,body,reactions,issue,issue_label,performed_via_github_app
https://github.com/simonw/datasette/issues/1289#issuecomment-812767460,https://api.github.com/repos/simonw/datasette/issues/1289,812767460,MDEyOklzc3VlQ29tbWVudDgxMjc2NzQ2MA==,9599,simonw,2021-04-03T00:48:26Z,2021-04-03T00:48:26Z,OWNER,"On my Mac `pytest-xdist` ran the test suite (minus two tests) in 59s, as opposed to 2m23s without xdist.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",849543502,Speed up tests with pytest-xdist,
https://github.com/simonw/datasette/issues/1289#issuecomment-812768915,https://api.github.com/repos/simonw/datasette/issues/1289,812768915,MDEyOklzc3VlQ29tbWVudDgxMjc2ODkxNQ==,9599,simonw,2021-04-03T00:59:15Z,2021-04-03T00:59:26Z,OWNER,"Looks like `-n auto` only detected two cores on GitHub Actions: https://github.com/simonw/datasette/runs/2257597137?check_suite_focus=true
```
============================= test session starts ==============================
platform linux -- Python 3.7.10, pytest-6.2.2, py-1.10.0, pluggy-0.13.1
SQLite: 3.31.1
rootdir: /home/runner/work/datasette/datasette, configfile: pytest.ini
plugins: xdist-2.2.1, timeout-1.4.2, forked-1.3.0, asyncio-0.14.0
gw0 I / gw1 I
gw0 [878] / gw1 [878]
```","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",849543502,Speed up tests with pytest-xdist,
https://github.com/simonw/datasette/issues/1289#issuecomment-812803256,https://api.github.com/repos/simonw/datasette/issues/1289,812803256,MDEyOklzc3VlQ29tbWVudDgxMjgwMzI1Ng==,9599,simonw,2021-04-03T03:29:25Z,2021-04-03T03:29:25Z,OWNER,"https://github.com/simonw/datasette/actions/runs/713207828 ran with `pytest-xdist` in 4m22s:

<img width=""1202"" alt=""Run_tests_in_CI_using_pytest-xdist__refs__1289_·_simonw_datasette_d63fc61"" src=""https://user-images.githubusercontent.com/9599/113466592-f151bf80-93f1-11eb-9d74-b830e96c19c8.png"">

Here's the test suite running on regular `pytest` in 5m13s:

<img width=""1162"" alt=""©_2017-2021_·_simonw_datasette_59ef4a2"" src=""https://user-images.githubusercontent.com/9599/113466606-00387200-93f2-11eb-95a3-24521c628cbe.png"">

Not a huge speed-up because there are only 2 available cores in the GitHub Actions environment, but still worthwhile - especially since this lets people run in parallel on their own laptops.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",849543502,Speed up tests with pytest-xdist,
https://github.com/simonw/datasette/pull/1290#issuecomment-812804178,https://api.github.com/repos/simonw/datasette/issues/1290,812804178,MDEyOklzc3VlQ29tbWVudDgxMjgwNDE3OA==,22429695,codecov[bot],2021-04-03T03:39:16Z,2021-04-03T03:41:29Z,NONE,"# [Codecov](https://codecov.io/gh/simonw/datasette/pull/1290?src=pr&el=h1) Report
> Merging [#1290](https://codecov.io/gh/simonw/datasette/pull/1290?src=pr&el=desc) (2fb1e42) into [main](https://codecov.io/gh/simonw/datasette/commit/87b583a128986982552421d2510e467e74ac5046?el=desc) (87b583a) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/simonw/datasette/pull/1290/graphs/tree.svg?width=650&height=150&src=pr&token=eSahVY7kw1)](https://codecov.io/gh/simonw/datasette/pull/1290?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##             main    #1290   +/-   ##
=======================================
  Coverage   91.51%   91.51%           
=======================================
  Files          34       34           
  Lines        4255     4255           
=======================================
  Hits         3894     3894           
  Misses        361      361           
```



------

[Continue to review full report at Codecov](https://codecov.io/gh/simonw/datasette/pull/1290?src=pr&el=continue).
> **Legend** - [Click here to learn more](https://docs.codecov.io/docs/codecov-delta)
> `Δ = absolute <relative> (impact)`, `ø = not affected`, `? = missing data`
> Powered by [Codecov](https://codecov.io/gh/simonw/datasette/pull/1290?src=pr&el=footer). Last update [87b583a...2fb1e42](https://codecov.io/gh/simonw/datasette/pull/1290?src=pr&el=lastupdated). Read the [comment docs](https://docs.codecov.io/docs/pull-request-comments).
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",849568079,Use pytest-xdist to speed up tests,
https://github.com/simonw/datasette/issues/916#issuecomment-812804998,https://api.github.com/repos/simonw/datasette/issues/916,812804998,MDEyOklzc3VlQ29tbWVudDgxMjgwNDk5OA==,9599,simonw,2021-04-03T03:47:45Z,2021-04-03T03:47:45Z,OWNER,I found one example of an implementation of reversed keyset pagination here: https://github.com/tvainika/objection-keyset-pagination/blob/cb21a493c96daa6e63c302efae6718d09aa11661/index.js#L74-L79,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",672421411,"Support reverse pagination (previous page, has-previous-items)",
https://github.com/simonw/datasette/issues/502#issuecomment-812813732,https://api.github.com/repos/simonw/datasette/issues/502,812813732,MDEyOklzc3VlQ29tbWVudDgxMjgxMzczMg==,5413548,louispotok,2021-04-03T05:16:54Z,2021-04-03T05:16:54Z,CONTRIBUTOR,"For what it's worth, if anyone finds this in the future, I was having the same issue. 

After digging through the code, it turned out that the database download is only available if it the db served in immutable mode, so `datasette serve -i xyz.db` rather than the doc's quickstart recommendation of `datasette serve xyz.db`.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",453131917,Exporting sqlite database(s)?,
https://github.com/simonw/datasette/issues/916#issuecomment-812940457,https://api.github.com/repos/simonw/datasette/issues/916,812940457,MDEyOklzc3VlQ29tbWVudDgxMjk0MDQ1Nw==,9599,simonw,2021-04-03T23:28:40Z,2021-04-03T23:28:40Z,OWNER,"I think my ideal implementation for this would be to reverse the order, grab the previous page-size-plus-one items, then return a `?_next=x` token that would provide the previous page sorted back in the expected default order.

The alternative would be to have a `?_previous=x` token which can be used to paginate backwards in reverse order, but I think this would be confusing as it would result in ""hit next page, then hit previous page"" returning you to a new state which features rows in the reverse order.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",672421411,"Support reverse pagination (previous page, has-previous-items)",
https://github.com/simonw/datasette/issues/916#issuecomment-812940907,https://api.github.com/repos/simonw/datasette/issues/916,812940907,MDEyOklzc3VlQ29tbWVudDgxMjk0MDkwNw==,9599,simonw,2021-04-03T23:33:41Z,2021-04-03T23:33:41Z,OWNER,"Let's figure out the SQL for this. The most complex case is probably this one: https://latest.datasette.io/fixtures/compound_three_primary_keys?_next=a%2Ch%2Cr

Here's the SQL for that page: https://latest.datasette.io/fixtures?sql=select+pk1%2C+pk2%2C+pk3%2C+content+from+compound_three_primary_keys+where+%28%28pk1+%3E+%3Ap0%29%0A++or%0A%28pk1+%3D+%3Ap0+and+pk2+%3E+%3Ap1%29%0A++or%0A%28pk1+%3D+%3Ap0+and+pk2+%3D+%3Ap1+and+pk3+%3E+%3Ap2%29%29+order+by+pk1%2C+pk2%2C+pk3+limit+101&p0=a&p1=h&p2=r

```sql
select pk1, pk2, pk3, content from compound_three_primary_keys where ((pk1 > :p0)
  or
(pk1 = :p0 and pk2 > :p1)
  or
(pk1 = :p0 and pk2 = :p1 and pk3 > :p2)) order by pk1, pk2, pk3 limit 101
```
Where `p0` is `a`, `p1` is `h` and `p2` is `r`.

Given the above, how would I figure out the correct previous link? It should be https://latest.datasette.io/fixtures/compound_three_primary_keys?_next=a%2Cd%2Cv - `a`, `d`, `v`.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",672421411,"Support reverse pagination (previous page, has-previous-items)",
https://github.com/simonw/datasette/issues/916#issuecomment-812941112,https://api.github.com/repos/simonw/datasette/issues/916,812941112,MDEyOklzc3VlQ29tbWVudDgxMjk0MTExMg==,9599,simonw,2021-04-03T23:35:55Z,2021-04-03T23:35:55Z,OWNER,"I tried flipping the direction of the sort and the comparison operators and got this: https://latest.datasette.io/fixtures?sql=select+pk1%2C+pk2%2C+pk3%2C+content+from+compound_three_primary_keys+where+%28%28pk1+%3C+%3Ap0%29%0D%0A++or%0D%0A%28pk1+%3D+%3Ap0+and+pk2+%3C+%3Ap1%29%0D%0A++or%0D%0A%28pk1+%3D+%3Ap0+and+pk2+%3D+%3Ap1+and+pk3+%3C+%3Ap2%29%29+order+by+pk1+desc%2C+pk2+desc%2C+pk3+desc+limit+1+offset+99&p0=a&p1=h&p2=r

```sql
select pk1, pk2, pk3, content from compound_three_primary_keys where ((pk1 < :p0)
  or
(pk1 = :p0 and pk2 < :p1)
  or
(pk1 = :p0 and pk2 = :p1 and pk3 < :p2)) order by pk1 desc, pk2 desc, pk3 desc limit 1 offset 99
```
Which returned `a-d-v` as desired. I messed around with it to find the `limit 1 offset 99` values.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",672421411,"Support reverse pagination (previous page, has-previous-items)",
https://github.com/simonw/datasette/issues/916#issuecomment-812941340,https://api.github.com/repos/simonw/datasette/issues/916,812941340,MDEyOklzc3VlQ29tbWVudDgxMjk0MTM0MA==,9599,simonw,2021-04-03T23:38:37Z,2021-04-03T23:38:37Z,OWNER,"Same query again with `a, d, v` returns 0 results, which is also as we would want: it signifies that we are back to the very first page: https://latest.datasette.io/fixtures?sql=select+pk1%2C+pk2%2C+pk3%2C+content+from+compound_three_primary_keys+where+%28%28pk1+%3C+%3Ap0%29%0D%0A++or%0D%0A%28pk1+%3D+%3Ap0+and+pk2+%3C+%3Ap1%29%0D%0A++or%0D%0A%28pk1+%3D+%3Ap0+and+pk2+%3D+%3Ap1+and+pk3+%3C+%3Ap2%29%29+order+by+pk1+desc%2C+pk2+desc%2C+pk3+desc+limit+1+offset+99&p0=a&p1=d&p2=v","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",672421411,"Support reverse pagination (previous page, has-previous-items)",
https://github.com/simonw/datasette/issues/916#issuecomment-812941818,https://api.github.com/repos/simonw/datasette/issues/916,812941818,MDEyOklzc3VlQ29tbWVudDgxMjk0MTgxOA==,9599,simonw,2021-04-03T23:43:11Z,2021-04-03T23:43:11Z,OWNER,"Relevant code is some of the most complex in all of Datasette.

https://github.com/simonw/datasette/blob/0a7621f96f8ad14da17e7172e8a7bce24ef78966/datasette/views/table.py#L530-L594

And

https://github.com/simonw/datasette/blob/0a7621f96f8ad14da17e7172e8a7bce24ef78966/datasette/views/table.py#L743-L771

I'll need to think hard about how to refactor this out into something more understandable before implementing previous links.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",672421411,"Support reverse pagination (previous page, has-previous-items)",
https://github.com/simonw/datasette/issues/1287#issuecomment-812935384,https://api.github.com/repos/simonw/datasette/issues/1287,812935384,MDEyOklzc3VlQ29tbWVudDgxMjkzNTM4NA==,9599,simonw,2021-04-03T22:38:33Z,2021-04-03T22:38:33Z,OWNER,"https://twitter.com/llanga/status/1378431719934681094 looks like I should wait for 3.9.4, out in a few days.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",849396758,Upgrade to Python 3.9.4,