As far as I can tell, sqlite3 executescript() does not respect isolation_level. Is that true? If so, I think it's worth mentioning in the doc. Or maybe it should respect isolation_level, not sure there's any particular reason not to.

Do you have a test case that could be used to verify a patch?
(Or even a full patch?)

Here's a test case

And here's a fix.

Unfortunately I think the change could break people's scripts. If they have isolation_level set (not None) and use executescript(), they will have to issue an explicit call to connection.commit().

executescript() could do the commit itself explicitly after running the sql, I suppose. Then the behavior is much like the old behavior, but at least you get the performance boost of running inside a transaction. (Substantial if you pass 10k insert statements to executescript(), or something like that.)

Or, we could not change the code, and instead change the documentation. The docs could suggest wrapping the sql script with "begin;" and "commit;".

Mentioning this behaviour in the documentation should be sufficient.

New changeset 76ed53ca7bf0d4a43099d9401af5fe9f75689885 by Miss Islington (bot) in branch '3.9':
bpo-30593: Doc'ed that executescript() disregards isolation level (GH-26220)
https://github.com/python/cpython/commit/76ed53ca7bf0d4a43099d9401af5fe9f75689885

New changeset 1f483c0c1b5a9fd1062bacc2aeba6bb0e00009b7 by Miss Islington (bot) in branch '3.10':
bpo-30593: Doc'ed that executescript() disregards isolation level (GH-26220)
https://github.com/python/cpython/commit/1f483c0c1b5a9fd1062bacc2aeba6bb0e00009b7