On poll 1.6 and Drupal 10.3.2 configured with Mysql/Mariadb and Transaction isolation level "REPEATABLE-READ" the following warning is being thrown in the status report:
Transaction isolation level
REPEATABLE-READ
The recommended level for Drupal is "READ COMMITTED". For this to work correctly, all tables must have a primary key. The following table(s) do not have a primary key: poll_vote. See the setting MySQL transaction isolation level page for more information.
In function poll_schema multiple primary keys ('pid', 'uid', 'hostname') are already defined for the poll_vote table, but it seems these are not recognized as primary key for the isolation level check.
Install poll 1.6 on Drupal 10.3.2 configured with Mysql/Mariadb and Transaction isolation level "REPEATABLE-READ" and visit Status page.
Add primary key on poll_vote table.
Active
1.6
Code
Can you re-try this on 2.0.x or the tagged alpha version.
https://git.drupalcode.org/project/poll/-/blob/2.0.x/poll.install?ref_ty...
Looks like poll_vote table has primary key
Feel free to re-open if still relevant. But I would assume this is indeed fixed.