Large tombstones creation

[Vlad <qa...@yahoo.com.INVALID>]

Hi,
I insert about 45000 rows to empty table in Python using prepared statements and IF NOT EXISTS. While reading after insert I get warnings likeServer warning: Read 5000 live rows and 33191 tombstone cells for query SELECT * FROM ...  LIMIT 5000 (see tombstone_warn_threshold)

How it can happen? I have several SASI indexes for this table, can this be a reason?
Regards, Vlad

Re: Large tombstones creation

[Christophe Schmitz <ch...@instaclustr.com>]

Hi Vlad,

Are you by any chance inserting null values? If so you will create
tombstones. The work around (Cassandra >= 2.2) is to use unset on your
bound statement (see https://issues.apache.org/jira/browse/CASSANDRA-7304)

Cheers,

Christophe

On 13 August 2017 at 20:48, Vlad <qa...@yahoo.com.invalid> wrote:

> Hi,
>
> I insert about 45000 rows to empty table in Python using prepared
> statements and IF NOT EXISTS. While reading after insert I get warnings like
> *Server warning: Read 5000 live rows and 33191 tombstone cells for query
> SELECT * FROM ...  LIMIT 5000 (see tombstone_warn_threshold)*
>
> How it can happen? I have several SASI indexes for this table, can this be
> a reason?
>
> Regards, Vlad
>



-- 


*Christophe Schmitz*
*Director of consulting EMEA*AU: +61 4 03751980 / FR: +33 7 82022899


<https://www.instaclustr.com>

<https://www.facebook.com/instaclustr>   <https://twitter.com/instaclustr>
<https://www.linkedin.com/company/instaclustr>

Read our latest technical blog posts here
<https://www.instaclustr.com/blog/>.

This email has been sent on behalf of Instaclustr Pty. Limited (Australia)
and Instaclustr Inc (USA).

This email and any attachments may contain confidential and legally
privileged information.  If you are not the intended recipient, do not copy
or disclose its content, but please reply to this email immediately and
highlight the error to the sender and then immediately delete the message.