After T401165, there are still some things we missed during the review process of T401165/PR#977:
- tou_acceptances and tou_versions don't seem to be linked. See here.
- tou_acceptances table uses string('version', 10), but the tou_versions doesn't. Here
the tou_version string will always be 10 chars (yyyy-mm-dd), I wonder if we should be using $table->char('tou_version', 10) which is a fixed width CHAR(10) rather than $table->string('tou_version', 10) which is a variable width VARCHAR(10). (comment from Ollie)
- id seems to be unnecessary and we can remove it, version is already unique. See here.