Overwriting non collections does not generate tombstones on compaction. — Jon Haddad Rustyrazorblade Consulting rustyrazorblade.com
On Wed, Oct 9, 2024 at 9:57 AM James Shaw <jxys...@gmail.com> wrote: > Hi, Naman: > How does the client side load large amounts of data ? Most > likely it has a retry policy, either by tool's default or by setting. If > it has a retry policy, will have duplicated records, after compaction, will > have tombstones. > > Another possibility, client set ttl, it will override table's ttl > setting, you may look at a few example data by ttl(pk_column_name), > writetime(pk_column_name) from the table. Sometimes, a surprise. > > > Thanks, > > James > > > On Wed, Oct 9, 2024 at 1:01 AM Jon Haddad <j...@rustyrazorblade.com> wrote: > >> Are you using collections? >> >> — >> Jon Haddad >> Rustyrazorblade Consulting >> rustyrazorblade.com >> >> >> On Tue, Oct 8, 2024 at 10:52 PM Naman kaushik <namankaush...@gmail.com> >> wrote: >> >>> Hi Community, >>> >>> We are currently using Cassandra version 4.1.3 and have encountered an >>> issue related to tombstone generation. We have two tables storing monthly >>> data: table_september and table_october. Each table has a TTL of 30 >>> days. >>> >>> For the month of October, data is being inserted into the table_october, >>> and we are seeing the following warning at the start of the month: >>> >>> *WARN [CompactionExecutor:22030] 2024-10-07 16:37:16,376 >>> BigTableWriter.java:274 - Writing 102594 tombstones to **table_october* >>> >>> *Here are a few things to note*: >>> >>> - No update or delete operations are being performed on the table. >>> - TTL is correctly set to 30 days, and the data being inserted is >>> within this time range, so the TTL shouldn't be the reason for >>> tombstones. >>> - No null values are being inserted in any column. >>> >>> We are still seeing tombstones being generated for the October table. >>> Does anyone have insights into what could be causing these tombstones, or >>> how we can prevent this from happening? >>> >>> Any help would be greatly appreciated! >>> >>> Thanks in advance. >>> >>
