>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3060135. --> Reported by: [xurizaemon](https://www.drupal.org/user/76026) >>> <p>It seems like the schema and DB index don't square up here, which AFAICT both prevents messages being delivered and prevents the DB update running (if there are existing entries).</p> <p><span class="drupalorg-gitlab-issue-link drupalorg-gitlab-link-wrapper"><a href="https://git.drupalcode.org/project/message_digest/-/work_items/3031714" class="drupalorg-gitlab-link">https://git.drupalcode.org/project/message_digest/-/work_items/3031714</a></span> added a unique index to <code>mid</code> but did not have a corresponding update to <a href="https://git.drupalcode.org/project/message_digest/blob/665d4a8ab592aa76965a219f7f42ed1b22af5117/message_digest.install#L15">message_digest_schema()</a> to make that column a serial.</p> <p>In <a href="https://git.drupalcode.org/project/message_digest/blob/665d4a8ab592aa76965a219f7f42ed1b22af5117/src/Plugin/Notifier/DigestBase.php#L108"><code>Drupal\message_digest\Plugin\Notifier\DigestBase::deliver()</code></a> we trigger a DB insert without setting mid, which is fine if mid is a serial and unique, OR if mid is not a serial and can store duplicates.</p> <p>AFAICT, this won't work. If the schema update is applied (which can only happen if there are no existing message_digest entries in the DB anyway?), then future digest messages will not be inserted to that table.</p> <p>Is this something which only works on MySQL perhaps? It still seems like it would not behave correctly.</p> <h3>When there's no pre-existing data in message_digest</h3> <p>Running message deliveries throws a lot of integrity constriant violation exceptions:</p> <blockquote><p> [error] Drupal\Core\Database\IntegrityConstraintViolationException: SQLSTATE[23505]: Unique violation: 7 ERROR: duplicate key value violates unique constraint "message_digest__mid__key"<br> DETAIL: Key (mid)=(17) already exists.: INSERT INTO message_digest (receiver, entity_type, entity_id, notifier, timestamp, mid) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5); Array() </p></blockquote> <h3>When there's already data in message_digest</h3> <p>DB is Postgres, and we have existing entries in the message_digest table. The column mid is not unique; far from it:</p> <pre>nzmathsd8=# select count(*), mid from message_digest group by mid having count(*) &gt; 1;<br>1924 1<br>1926 2<br>1926 3<br>1926 4</pre><p>I don't think we can rely on {message_digest}.mid being unique based on the schema, but <a href="https://git.drupalcode.org/project/message_digest/commit/022e5b2">022e5b2</a> merged in <span class="drupalorg-gitlab-issue-link drupalorg-gitlab-link-wrapper"><a href="https://git.drupalcode.org/project/message_digest/-/work_items/3031714" class="drupalorg-gitlab-link">https://git.drupalcode.org/project/message_digest/-/work_items/3031714</a></span> treats it as such.</p> <pre>vagrant@example:/vagrant$ drush updatedb<br> -------- ------------ --------------- ---------------------------------------- <br>&nbsp; Module&nbsp;&nbsp; Update ID&nbsp;&nbsp;&nbsp; Type&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Description&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br> -------- ------------ --------------- ---------------------------------------- <br>&nbsp; messag&nbsp;&nbsp; 8102&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; hook_update_n&nbsp;&nbsp; Add unique index to mid field.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br>&nbsp; e_dige&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br>&nbsp; st&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <br> -------- ------------ --------------- ---------------------------------------- <br><br> Do you wish to run the specified pending updates? (yes/no) [yes]:<br> &gt; yes<br><br>&gt;&nbsp; [notice] Update started: message_digest_update_8102<br>&gt;&nbsp; [error]&nbsp; SQLSTATE[23505]: Unique violation: 7 ERROR:&nbsp; could not create unique index "message_digest__mid__key" <br>&gt; DETAIL:&nbsp; Key (mid)=(1) is duplicated.: ALTER TABLE {message_digest} ADD CONSTRAINT message_digest__mid__key UNIQUE (mid); Array<br>&gt; (<br>&gt; )<br>&gt;&nbsp; <br>&gt;&nbsp; [error]&nbsp; Update failed: message_digest_update_8102 <br> [error]&nbsp; Update aborted by: message_digest_update_8102 <br> [error]&nbsp; Finished performing updates. </pre>