my intuition is leave the plans alone. when actually execute the TABLESCAN
PLAN, send it to two targets.
refer to the csv example.
On Tue, Oct 22, 2019 at 9:26 PM Juan Pan wrote:
> Hi Danny and Julian
>
>
> Thanks, i did some researches after listened to your suggestions. It seems
> not an easy
Hi Danny and Julian
Thanks, i did some researches after listened to your suggestions. It seems not
an easy thing for me, but i will learn Calcite and Flink more and think about
your thoughts.
Best wishes,
Trista
Juan Pan
panj...@apache.org
Juan Pan(Trista), Apache ShardingSphere
On
In this case, you could rewrite your query to include a UNION and
select data from the two sources together. That would likely be the
easiest path forward.
--
Michael Mior
mm...@apache.org
Le lun. 21 oct. 2019 à 22:36, Juan Pan a écrit :
>
> Hi everyone,
>
>
> Thanks for your attention. I can
You may need a computation framework like Apache Flink. Use MySQL and Cassandra
as connector/dataSource and write the results to your sink.
Best,
Danny Chan
在 2019年10月22日 +0800 AM10:36，Juan Pan ，写道：
> Hi everyone,
>
>
> Thanks for your attention. I can not get a clear result after read most of
Thanks for your rely.
`SELECT * FROM tb WHERE id = 1`
can be converted into `UNION ALL`, but i am worried how to handle some
aggregation SQLs, e.g `SELECT AVG(NUM) FROM tb`.
Juan Pan
panj...@apache.org
Juan Pan(Trista), Apache ShardingSphere
On 10/22/2019 11:04，Julian Hyde wrote：
Not
Not currently, but it wouldn’t be too much work.
Consider a similar query:
SELECT * FROM mysqlTable
UNION ALL
SELECT * FROM cassandraTable
This would convert into an EnumerableUnion which would send sub-queries to the
two back ends and combine the results.
You’d need a new relational operator
Hi everyone,
Thanks for your attention. I can not get a clear result after read most of
Calcite document. So i send this email for your suggestion.
Suppose there are two data storages, e.g, MySQL and Cassandra behind Calcite,
and data is separately stored in two of them, can i execute a
