Btw, if you seen the number of tombstones that is a multiply of number of
scanned rows, like in your case - that’s a explicit signal of either null
inserts, or non frozen collections...
On Fri 21. Aug 2020 at 20:21, Attila Wind wrote:
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> right! silly me (regarding "can't have
right! silly me (regarding "can't have null for clustering column") :-)
OK code is modified, we stopped using NULL on that column. In a few days
we will see if this was the cause.
Thanks for the useful info eveyrone! Helped a lot!
Attila Wind
http://www.linkedin.com/in/attilaw
Mobile: +49 17
inserting null for any column will generate the tombstone (and you can't
have null for clustering column, except case when it's an empty partition
with static column).
if you're really inserting the new data, not overwriting existing one - use
UNSET instead of null
On Fri, Aug 21, 2020 at 10:45 AM
Thanks a lot! I will process every pointers you gave - appreciated!
1. we do have collection column in that table but that is (we have only
1 column) a frozen Map - so I guess "Tombstones are also implicitly
created any time you insert or update a row which has an (unfrozen)
collection column:
On Fri, Aug 21, 2020 at 9:43 AM Tobias Eriksson
wrote:
> Isn’t it so that explicitly setting a column to NULL also result in a
> tombstone
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True, thanks for pointing that out!
Then as mentioned the use of list,set,map can also result in tombstones
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> See
> https://www.instaclustr.com/cassandr
Isn’t it so that explicitly setting a column to NULL also result in a tombstone
Then as mentioned the use of list,set,map can also result in tombstones
See
https://www.instaclustr.com/cassandra-collections-hidden-tombstones-and-how-to-avoid-them/
-Tobias
From: Oleksandr Shulgin
Reply to: "user@
On Fri, Aug 21, 2020 at 7:57 AM Attila Wind wrote:
> Hi Cassandra Gurus,
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> Recently I captured a very interesting warning in the logs saying
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> 2020-08-19 08:08:32.492
> [cassandra-client-keytiles_data_webhits-nio-worker-2] WARN
> com.datastax.driver.core.RequestHandler - Query '[3 bound value
Tombstones could be not only generated by deletes. this happens when you:
- When insert or full update of a non-frozen collection occurs, such as
replacing the value of the column with another value like the UPDATE table
SET field = new_value …, Cassandra inserts a tombstone marker to pre