https://community.cloudera.com/t5/Support-Questions/Does-TTL-in-Hbase-require-Major-Compaction/m-p/214167#M176082 <P> The docs say:</P><P style="margin-left: 20px;">When an explicit deletion occurs in HBase, the data is not actually deleted. Instead, a <EM>tombstone</EM> marker is written. The tombstone marker prevents the data from being returned with queries. During a major compaction, the data is actually deleted, and the tombstone marker is removed from the StoreFile. <STRONG>If the deletion happens because of an expired TTL, no tombstone is created. Instead, the expired data is filtered out and is not written back to the compacted StoreFile.</STRONG></P><P>What does "expired data is filtered out and is not written back to the compacted StoreFile." mean?</P><P>I have done some testing with TTL. I put 1 million records in a database. I checked the file size. Then I set the ttl to 1 minute and all the data dissapeared (the actual file got much smaller). Our database has major compaction shut off.</P><P>Does a major compaction have to happen with TTL?</P> Thu, 22 Jun 2017 00:53:45 GMT juchems_mark_e 2017-06-22T00:53:45Z