Using DSE Search/Solr
When you update a table using CQL, the Solr document is updated. Re-indexing occurs automatically after an update.
Writes are durable. A Solr API client writes data to Cassandra first, and then Cassandra updates indexes. All writes to a replica node are recorded both in memory and in a commit log before they are acknowledged as a success. If a crash or server failure occurs before the memory tables are flushed to disk, the commit log is replayed on restart to recover any lost writes.
The commit log replaces the Solr updatelog, which is not supported in DSE Search/Solr. Consequently, atomic updates and real-time get that require the updateLog are not supported. In Cassandra, a write is atomic at the row-level, meaning inserting or updating columns in a row is treated as one write operation.
The Solr index update operation is similar to a Cassandra index update. If the old column value was still in the Cassandra memtable, Cassandra removes the index entry; otherwise, the old entry remains to be purged by compaction. If a read sees a stale index entry before compaction purges it, the reader thread invalidates it. You can also trigger the expiration of search data.