Polybase Use Cases

James Serra talks about Polybase use cases:

For federated queries: “N” requires all data from the source to be copied into SQL Server 2016 and then filtered.  For “Y”, the query is pushed down into the data source and only the results are returned back, which can be much faster for large amounts of data.

I mention “Maybe” for age out data in SQL DW as you can use PolyBase to access the aged-out data in blob or Azure Data Lake Storage (ADLS), but it will have to import all the data so may have slower performance (which is usually ok for accessing data that is aged-out).  For SQL Server 2016, it will have to import the data unless you use HDP/Cloudera, in which case the creation of the MapReduce job will add overhead.

The thing that I like about this chart is that the new Polybase sources (SQL Server, Oracle, Teradata, Mongo, and generic ODBC) do support predicate pushdown.  For large data sets, that’s huge:  it lets the database engine on the opposite end do as much filtering as possible before sending results back to your SQL Server head node.

Related Posts

Polybase And HDInsight

I have a post up on trying to integrate Polybase with HDInsight: But now we run into a problem:  there are certain ports which need to be open for Polybase to work.  This includes port 50010 on each of the data nodes against which we want to run MapReduce jobs.  This goes back to the issue […]

Read More

Polybase And RPC Protection

Casey Karst announces that Polybase supports Hadoop RPC protection: Supporting this configuration allows PolyBase to connect and query Hadoop clusters that have wire encryption turned on. This enables a secure connection between Hadoop and SQL Server; as well as, among the Hadoop Data Nodes. To connect to a Hadoop cluster with the hadoop.rpc.protection set to […]

Read More

Categories

March 2017
MTWTFSS
« Feb Apr »
 12345
6789101112
13141516171819
20212223242526
2728293031