Question is specifically about primary and secondary partitions.

So in case of replicated cache ignite scans primary and secondary
partitions of any one of the node of the cluster to to fetch the data.

But is it the case with partitioned cache.
I mean in case of partitioned cache when SQL is executed, does ignite scan
primary as well as secondary partitions of each node in the cluster or it
just scans primary partitions of all the nodes in the cluster as the query
is being executed on all nodes?

On Fri 25 Oct, 2019, 10:46 PM <alexanderko...@gmail.com wrote:

> Hi,
>
>
>
>    If a query is executed against a fully *REPLICATED* data then Ignite
> will send it to a single cluster node and run it over the local data there.
>
>
>
>
>
>
>
>  if a query is executed over a *PARTITIONED* data, then the execution
> flow will be the following:
>
> The query will be parsed and split into multiple map queries and a single
> reduce query.
>
> ·         All the map queries are executed on all the nodes where
> required data resides.
>
> ·         All the nodes provide result sets of local execution to the
> query initiator (reducer) that, in turn, will accomplish the reduce phase
> by properly merging provided result sets.
>
>
>
>
>
>
>
>  More information here:
> https://apacheignite-sql.readme.io/docs/how-ignite-sql-works
>
> Thanks, Alex
>
>
>
> *From:* Prasad Bhalerao <prasadbhalerao1...@gmail.com>
> *Sent:* Friday, October 25, 2019 1:31 AM
> *To:* user@ignite.apache.org
> *Subject:* Query execution in ignite
>
>
>
> Hi,
>
>
>
> When SQL is executed, does ignite always scan only primary partitions of
> all available nodes in cluster irrespective of cache mode partitioned or
> replicated?
>
>
>
>
>
>
>
> Thanks ,
>
> Prasad
>

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