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/sqlite-utils/issues/365#issuecomment-1008166084,https://api.github.com/repos/simonw/sqlite-utils/issues/365,1008166084,IC_kwDOCGYnMM48F2TE,536941,fgregg,2022-01-08T22:32:47Z,2022-01-08T22:32:47Z,CONTRIBUTOR,or using “ pragma optimize”,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096558279,create-index should run analyze after creating index,
https://github.com/simonw/sqlite-utils/issues/365#issuecomment-1008164786,https://api.github.com/repos/simonw/sqlite-utils/issues/365,1008164786,IC_kwDOCGYnMM48F1-y,536941,fgregg,2022-01-08T22:24:19Z,2022-01-08T22:24:19Z,CONTRIBUTOR,the out-of-date scenario you describe could be addressed by automatically adding an analyze to the insert or convert commands if they implicate an index,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096558279,create-index should run analyze after creating index,
https://github.com/simonw/sqlite-utils/issues/365#issuecomment-1008164116,https://api.github.com/repos/simonw/sqlite-utils/issues/365,1008164116,IC_kwDOCGYnMM48F10U,536941,fgregg,2022-01-08T22:18:57Z,2022-01-08T22:18:57Z,CONTRIBUTOR,"the table with the query ran so bad was about 50k.
i think the scenario should not be worse than no stats.
i also did not know that sqlite was so different from postgres and needed an explicit analyze call.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096558279,create-index should run analyze after creating index,
https://github.com/simonw/sqlite-utils/issues/365#issuecomment-1008163050,https://api.github.com/repos/simonw/sqlite-utils/issues/365,1008163050,IC_kwDOCGYnMM48F1jq,9599,simonw,2022-01-08T22:10:51Z,2022-01-08T22:10:51Z,OWNER,"Is there a downside to having a `sqlite_stat1` table if it has wildly incorrect statistics in it?
Imagine the following sequence of events:
- User imports a few records, creating the table, using `sqlite-utils insert`
- User runs `sqlite-utils create-index ...` which also creates and populates the `sqlite_stat1` table
- User runs `insert` again to populate several million new records
The user now has a database file with several million records and a statistics table that is wildly out of date, having been populated when they only had a few.
Will this result in surprisingly bad query performance compared to it that statistics table did not exist at all?
If so, I lean much harder towards `ANALYZE` as a strictly opt-in optimization, maybe with the `--analyze` option added to `sqlite-utils insert` top to help users opt in to updating their statistics after running big inserts.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096558279,create-index should run analyze after creating index,
https://github.com/simonw/sqlite-utils/issues/365#issuecomment-1008161965,https://api.github.com/repos/simonw/sqlite-utils/issues/365,1008161965,IC_kwDOCGYnMM48F1St,536941,fgregg,2022-01-08T22:02:56Z,2022-01-08T22:02:56Z,CONTRIBUTOR,"for options 2 and 3, i would worry about discoverablity.
in other db’s it is not necessary to explicitly call analyze for most indices. ie for postgres
> The system regularly collects statistics on all of a table's columns. Newly-created non-expression indexes can immediately use these statistics to determine an index's usefulness.
i suppose i would propose raising a warning if the stats table is created that explains what is going on and informs users about a —no-analyze argument.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096558279,create-index should run analyze after creating index,
https://github.com/simonw/sqlite-utils/issues/366#issuecomment-1008158616,https://api.github.com/repos/simonw/sqlite-utils/issues/366,1008158616,IC_kwDOCGYnMM48F0eY,9599,simonw,2022-01-08T21:35:32Z,2022-01-08T21:35:32Z,OWNER,"Built a prototype in a branch, see #367.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096563265,Python library methods for calling ANALYZE,
https://github.com/simonw/sqlite-utils/issues/365#issuecomment-1008158357,https://api.github.com/repos/simonw/sqlite-utils/issues/365,1008158357,IC_kwDOCGYnMM48F0aV,9599,simonw,2022-01-08T21:33:07Z,2022-01-08T21:33:07Z,OWNER,"The one thing that worries me a little bit about doing this by default is that it adds a surprising new table to the database - it may be confusing to users if they run `create-index` and their database suddenly has a new `sqlite_stat1` table, see https://github.com/simonw/sqlite-utils/issues/366#issuecomment-1008157132
Options here are:
- Do it anyway. People can tolerate a surprise table appearing when they create an index.
- Only run `ANALYZE` if the user says `sqlite-utils create-index ... --analyze`
- Use the `--analyze` option, but also automatically run `ANALYZE` if they create an index and the database they are working with already has a `sqlite_stat1` table
I'm currently leading towards that third option - @fgregg any thoughts?","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096558279,create-index should run analyze after creating index,
https://github.com/simonw/datasette/issues/1587#issuecomment-1008157998,https://api.github.com/repos/simonw/datasette/issues/1587,1008157998,IC_kwDOBm6k_c48F0Uu,9599,simonw,2022-01-08T21:29:54Z,2022-01-08T21:29:54Z,OWNER,Relevant code: https://github.com/simonw/datasette/blob/00a2895cd2dc42c63846216b36b2dc9f41170129/datasette/database.py#L339-L354,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1097040427,Add `sqlite_stat1`(-4) tables to hidden table list,
https://github.com/simonw/datasette/issues/1587#issuecomment-1008157908,https://api.github.com/repos/simonw/datasette/issues/1587,1008157908,IC_kwDOBm6k_c48F0TU,9599,simonw,2022-01-08T21:29:06Z,2022-01-08T21:29:06Z,OWNER,"Depending on the SQLite version (and compile options) that ran `ANALYZE` these can be called:
- `sqlite_stat1`
- `sqlite_stat2`
- `sqlite_stat3`
- `sqlite_stat4`","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1097040427,Add `sqlite_stat1`(-4) tables to hidden table list,
https://github.com/simonw/sqlite-utils/issues/366#issuecomment-1008157132,https://api.github.com/repos/simonw/sqlite-utils/issues/366,1008157132,IC_kwDOCGYnMM48F0HM,9599,simonw,2022-01-08T21:23:08Z,2022-01-08T21:25:05Z,OWNER,"Running `ANALYZE` creates a new visible table called `sqlite_stat1`: https://www.sqlite.org/fileformat.html#the_sqlite_stat1_table
This should be added to the default list of hidden tables in Datasette.
It looks something like this:
| tbl | idx | stat |
|---------------------------------|------------------------------------|-----------|
| _counts | sqlite_autoindex__counts_1 | 5 1 |
| global-power-plants_fts_config | global-power-plants_fts_config | 1 1 |
| global-power-plants_fts_docsize | | 33643 |
| global-power-plants_fts_idx | global-power-plants_fts_idx | 199 40 1 |
| global-power-plants_fts_data | | 136 |
| global-power-plants | ""global-power-plants_owner"" | 33643 4 |
| global-power-plants | ""global-power-plants_country_long"" | 33643 202 |
> In each such row, the sqlite_stat.stat column will be a string consisting of a list of integers followed by zero or more arguments. The first integer in this list is the approximate number of rows in the index. (The number of rows in the index is the same as the number of rows in the table, except for partial indexes.) The second integer is the approximate number of rows in the index that have the same value in the first column of the index. The third integer is the number number of rows in the index that have the same value for the first two columns. The N-th integer (for N>1) is the estimated average number of rows in the index which have the same value for the first N-1 columns. For a K-column index, there will be K+1 integers in the stat column. If the index is unique, then the last integer will be 1. ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1096563265,Python library methods for calling ANALYZE,
https://github.com/simonw/sqlite-utils/issues/364#issuecomment-1008155916,https://api.github.com/repos/simonw/sqlite-utils/issues/364,1008155916,IC_kwDOCGYnMM48Fz0M,9599,simonw,2022-01-08T21:16:46Z,2022-01-08T21:16:46Z,OWNER,"No, `chunks()` seems to work OK in the test I just added.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1095570074,`--batch-size 1` doesn't seem to commit for every item,
https://github.com/simonw/sqlite-utils/issues/364#issuecomment-1008154873,https://api.github.com/repos/simonw/sqlite-utils/issues/364,1008154873,IC_kwDOCGYnMM48Fzj5,9599,simonw,2022-01-08T21:11:55Z,2022-01-08T21:11:55Z,OWNER,"I'm suspicious that the `chunks()` utility function may not be working correctly:
```pycon
In [10]: [list(d) for d in list(chunks('abc', 5))]
Out[10]: [['a'], ['b'], ['c']]
In [11]: [list(d) for d in list(chunks('abcdefghi', 5))]
Out[11]: [['a'], ['b'], ['c'], ['d'], ['e'], ['f'], ['g'], ['h'], ['i']]
In [12]: [list(d) for d in list(chunks('abcdefghi', 3))]
Out[12]: [['a'], ['b'], ['c'], ['d'], ['e'], ['f'], ['g'], ['h'], ['i']]
```","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1095570074,`--batch-size 1` doesn't seem to commit for every item,
https://github.com/simonw/sqlite-utils/issues/364#issuecomment-1008153586,https://api.github.com/repos/simonw/sqlite-utils/issues/364,1008153586,IC_kwDOCGYnMM48FzPy,9599,simonw,2022-01-08T21:06:15Z,2022-01-08T21:06:15Z,OWNER,"I added a print statement after `for query, params in queries_and_params` and confirmed that something in the code is waiting until 16 records are available to be inserted and then executing the inserts, even with `--batch-size 1`.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1095570074,`--batch-size 1` doesn't seem to commit for every item,
https://github.com/simonw/sqlite-utils/issues/364#issuecomment-1008151884,https://api.github.com/repos/simonw/sqlite-utils/issues/364,1008151884,IC_kwDOCGYnMM48Fy1M,9599,simonw,2022-01-08T20:59:21Z,2022-01-08T20:59:21Z,OWNER,"(That Heroku example doesn't record the timestamp, which limits its usefulness)","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1095570074,`--batch-size 1` doesn't seem to commit for every item,
https://github.com/simonw/sqlite-utils/issues/364#issuecomment-1008143248,https://api.github.com/repos/simonw/sqlite-utils/issues/364,1008143248,IC_kwDOCGYnMM48FwuQ,9599,simonw,2022-01-08T20:34:12Z,2022-01-08T20:34:12Z,OWNER,Built that tool: https://github.com/simonw/stream-delay and https://pypi.org/project/stream-delay/,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1095570074,`--batch-size 1` doesn't seem to commit for every item,
https://github.com/simonw/sqlite-utils/issues/364#issuecomment-1008129841,https://api.github.com/repos/simonw/sqlite-utils/issues/364,1008129841,IC_kwDOCGYnMM48Ftcx,9599,simonw,2022-01-08T20:04:42Z,2022-01-08T20:04:42Z,OWNER,"It would be easier to test this if I had a utility for streaming out a file one line at a time.
A few recipes for this in https://superuser.com/questions/526242/cat-file-to-terminal-at-particular-speed-of-lines-per-second - I'm going to build a quick `stream-delay` tool though.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1095570074,`--batch-size 1` doesn't seem to commit for every item,
https://github.com/simonw/datasette/pull/1574#issuecomment-1007844190,https://api.github.com/repos/simonw/datasette/issues/1574,1007844190,IC_kwDOBm6k_c48Ente,536941,fgregg,2022-01-08T00:42:12Z,2022-01-08T00:42:12Z,CONTRIBUTOR,is there a reason to not always use the slim option?,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",1084193403,introduce new option for datasette package to use a slim base image,