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Posted to user@cassandra.apache.org by Vladimir Yudovin <vl...@winguzone.com> on 2017/08/15 14:03:46 UTC
SASI index returns no results
Hi,
I recently encountered with strange issue.
Assuming there is table
id PRIMARY KEY
indexed text
column text
CREATE custom index on table(indexed) using '...SASIIndex'
I inserted row like id=0, indexed='string1', column='just string'
When I did SELECT * FROM table WHERE id=0 AND indexed='string1' no rows is returned, while SELECT * FROM table WHERE id=0 AND column =' just string' ALLOW FILTERING returned the row.
In reality this table consist about 70 columns, 20M rows and probably total 30G on disk with RF=2 and three nodes. I guess this issue is somehow linked to memory usage, as I run some different heavy queries, then cluster become unresponsible to cqlsh and nodetool. I sow GC messages in gc.log, so I restated cluster and all returned to normal.
I would expect the whole query to fail with timeout or some error message, but not to silently return zero rows.
Any thoughts?
Best regards, Vladimir Yudovin,
Winguzone - Cloud Cassandra Hosting
Re: SASI index returns no results
Posted by Fay,
,
Storage,
,
<fa...@coupang.com>.
SASI is in early experiment and had many major problems. for example,
"nodetool repair breaks SASI index"
https://issues.apache.org/jira/browse/CASSANDRA-13403
"OOM when using SASI index"
https://issues.apache.org/jira/browse/CASSANDRA-12662
I would not use SASI index for production.
Fay
On Tue, Aug 15, 2017 at 7:03 AM, Vladimir Yudovin <vl...@winguzone.com>
wrote:
> Hi,
>
> I recently encountered with strange issue.
> Assuming there is table
>
> id PRIMARY KEY
> indexed text
> column text
>
> CREATE custom index on table(indexed) using '...SASIIndex'
>
> I inserted row like *id=0, indexed='string1', column='just string'*
>
> When I did *SELECT * FROM table WHERE id=0 AND indexed='string1' *no rows
> is returned, while *SELECT * FROM table WHERE id=0 AND column =' just
> string' ALLOW FILTERING* returned the row.
>
> In reality this table consist about 70 columns, 20M rows and probably
> total 30G on disk with RF=2 and three nodes. I guess this issue is somehow
> linked to memory usage, as I run some different heavy queries, then cluster
> become unresponsible to cqlsh and nodetool. I sow GC messages in gc.log, so
> I restated cluster and all returned to normal.
>
> I would expect the whole query to fail with timeout or some error message,
> but not to silently return zero rows.
> Any thoughts?
>
> Best regards, Vladimir Yudovin,
> *Winguzone <https://winguzone.com?from=list> - Cloud Cassandra Hosting*
>
>
Re: SASI index returns no results
Posted by Erick Ramirez <fl...@gmail.com>.
Have you tried tracing (TRACING ON) the query? That would usually give you
clues as to where it's failing. Cheers!
On Wed, Aug 16, 2017 at 12:03 AM, Vladimir Yudovin <vl...@winguzone.com>
wrote:
> Hi,
>
> I recently encountered with strange issue.
> Assuming there is table
>
> id PRIMARY KEY
> indexed text
> column text
>
> CREATE custom index on table(indexed) using '...SASIIndex'
>
> I inserted row like *id=0, indexed='string1', column='just string'*
>
> When I did *SELECT * FROM table WHERE id=0 AND indexed='string1' *no rows
> is returned, while *SELECT * FROM table WHERE id=0 AND column =' just
> string' ALLOW FILTERING* returned the row.
>
> In reality this table consist about 70 columns, 20M rows and probably
> total 30G on disk with RF=2 and three nodes. I guess this issue is somehow
> linked to memory usage, as I run some different heavy queries, then cluster
> become unresponsible to cqlsh and nodetool. I sow GC messages in gc.log, so
> I restated cluster and all returned to normal.
>
> I would expect the whole query to fail with timeout or some error message,
> but not to silently return zero rows.
> Any thoughts?
>
> Best regards, Vladimir Yudovin,
> *Winguzone <https://winguzone.com?from=list> - Cloud Cassandra Hosting*
>
>