Dspace对RDBMS和SOLR的双写与并发性

I'd like to know how dspace manage indexing in both the database and solr while supporting concurrency. In other words, if 2 individuals try to write at the same time, on the same item (e.g. changing metadata), how do dspace ensure that the index will not be desynchronized with the database. I'd like to know how dspace manage indexing in