SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1-510' for key 'PRIMARY', query was: INSERT  INTO `temp_catalog_category_tree_index_40850d82` (`parent_id`,`child_id`) VALUES (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?,
Product Categories indexer process unknown error:
SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1-510' for key 'PRIMARY', query was: INSERT  INTO `temp_catalog_category_tree_index_cebdbaaf` (`parent_id`,`child_id`) VALUES (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?, ?), (?,
Catalog Rule Product index has been rebuilt successfully in 00:00:00

mysql> select row_id, entity_id, path from catalog_category_entity where path like '1/1/%';

+--------+-----------+---------+
| row_id | entity_id | path    |
+--------+-----------+---------+
|    510 |       510 | 1/1/510 |
|    511 |       511 | 1/1/511 |
+--------+-----------+---------+
2 rows in set (0.01 sec)
Resolution: not a bug
PLEASE PERFORM THE FOLLOWING ACTIONS:
execute the next SQL:
update catalog_category_entity set path = replace(path, '1/1/', '1/')
where path like '1/1/%';