id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,pull_request,body,repo,type,active_lock_reason,performed_via_github_app,reactions,draft,state_reason
1383646615,I_kwDOCGYnMM5SeMWX,491,Ability to merge databases and tables,8904453,open,0,,,7,2022-09-23T11:10:55Z,2023-06-14T22:14:24Z,,NONE,,"Hi! Let me firstly say that I am a big fan of your work -- I follow your tweets and blog posts with great interest 😄.

Now onto the matter at hand: I think it would be great if `sqlite-utils` included a `merge` or `combine` command, with the purpose of combining different SQLite databases into a single SQLite database. This way, the newly ""merged"" database would contain all differently named tables contained in the databases to be merged as-is, as well a concatenation of all tables of the same name.

This could look something like this:

```bash
sqlite-utils merge cats.db dogs.db > animals.db
```

I imagine this is rather straightforward if all databases involved in the merge contain differently named tables (i.e. no chance of conflicts), but things get slightly more complicated if two or more of the databases to be merged contain tables with the same name. Not only do you have to ""do something"" with the primary key(s), but these tables could also simply have different schemas (and therefore be incompatible for concatenation to begin with).

Anyhow, I would love your thoughts on this, and, if you are open to it, work together on the design and implementation!",140912432,issue,,,"{""url"": ""https://api.github.com/repos/simonw/sqlite-utils/issues/491/reactions"", ""total_count"": 2, ""+1"": 2, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,
1733198948,I_kwDOCGYnMM5nToRk,555,Filter table by a large bunch of ids,10843208,open,0,,,1,2023-05-31T00:29:51Z,2023-06-14T22:01:57Z,,NONE,,"Hi! this might be a question related to both SQLite & sqlite-utils, and you might be more experienced with them.

I have a large bunch of ids, and I'm wondering which is the best way to query them in terms of performance, and simplicity if possible.

The naive approach would be something like `select * from table where rowid in (?, ?, ?...)` but that wouldn't scale if ids are >1k.

Another approach might be creating a temp table, or in-memory db table, insert all ids in that table and then join with the target one.

I failed to attach an in-memory db both using sqlite-utils, and plain sql's execute(), so my closest approach is something like,

```python
def filter_existing_video_ids(video_ids):
    db = get_db()  # contains a ""videos"" table
    db.execute(""CREATE TEMPORARY TABLE IF NOT EXISTS tmp (video_id TEXT NOT NULL PRIMARY KEY)"")
    db[""tmp""].insert_all([{""video_id"": video_id} for video_id in video_ids])
    for row in db[""tmp""].rows_where(""video_id not in (select video_id from videos)""):
        yield row[""video_id""]
    db[""tmp""].drop()
```

That kinda worked, I couldn't find an option in sqlite-utils's `create_table()` to tell it's a temporary table. Also, `tmp` table is not dropped finally, neither using `.drop()` despite being created with the keyword `TEMPORARY`. I believe it should be automatically dropped after connection/session ends though I read.",140912432,issue,,,"{""url"": ""https://api.github.com/repos/simonw/sqlite-utils/issues/555/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,