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 <[email protected]> wrote:
> Are you using collections?
>
> —
> Jon Haddad
> Rustyrazorblade Consulting
> rustyrazorblade.com
>
>
> On Tue, Oct 8, 2024 at 10:52 PM Naman kaushik <[email protected]>
> 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.
>>
>
