>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #1971710. --> Reported by: [phillamb168](https://www.drupal.org/user/51152) >>> <p>In the following example, it's possible to see that the Sub_part for the unique key 'u_provider_type_base_id' is limited to 64 characters:</p> <pre>mysql&gt; show index from scald_atoms;<br>+-------------+------------+-------------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+<br>| Table&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | Non_unique | Key_name&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |<br>+-------------+------------+-------------------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+<br>| scald_atoms |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 | PRIMARY&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; 1 | sid&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | A&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 40 |&nbsp;&nbsp;&nbsp;&nbsp; NULL | NULL&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | BTREE&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |<br>| scald_atoms |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 | u_provider_type_base_id |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 1 | provider&nbsp;&nbsp;&nbsp; | A&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 2 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 64 | NULL&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | BTREE&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |<br>| scald_atoms |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 | u_provider_type_base_id |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 2 | type&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | A&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 2 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 64 | NULL&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; | BTREE&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |<br>| scald_atoms |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 0 | u_provider_type_base_id |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 3 | base_id&nbsp;&nbsp;&nbsp;&nbsp; | A&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 40 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 64 | NULL&nbsp;&nbsp; | YES&nbsp; | BTREE&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; |</pre><p>This can cause Duplicate Entry / Integrity constraint violations for a significantly long provider, type, or base_id. For example, we encountered this bug when creating two separate DMCloud videos, one with a base_id (URL, in this case) of:<br> <a href="http://api.dmcloud.net/player/embed/reallylonghashcodeherethatissomewhatsimilar">http://api.dmcloud.net/player/embed/reallylonghashcodeherethatissomewhatsimilar</a><br> and another with a base_id of:<br> <a href="http://api.dmcloud.net/player/embed/reallylonghashcodeherethatisnolongersimilar">http://api.dmcloud.net/player/embed/reallylonghashcodeherethatisnolongersimilar</a></p> <p>For our case, with a provider of 'scald_sgv' and a type of 'video,' (and keeping in mind the 64 char limit), we thus have a unique key of:<br> scald_sgv-video-<a href="http://api.dmcloud.net/player/embed/reallylongha">http://api.dmcloud.net/player/embed/reallylongha</a><br> for the first, and for the second:<br> scald_sgv-video-<a href="http://api.dmcloud.net/player/embed/reallylongha">http://api.dmcloud.net/player/embed/reallylongha</a></p> <p>Thus the integrity constant violation. It seems that the 'easy' solution is to increase the unique key to, at a minimum, 128 characters each. I am rolling a patch to the scald.install file that will handle this (posting soon).</p>