The Greenplum ORCA Optimizer

In January Greenplum rolled out a new query optimizer. This is very cool and very advanced stuff. Query optimization is a search problem… in a perfect world you would search through the space of all possible plans for any query and choose the least expensive plan. But the time required to iterate through all possible…

Netezza Zone Maps and I/O Avoidance

A reader recently wrote to me and asked about Netezza: “why does everyone insist that these (zone maps) tell you where ‘not to look’ when hunting for data?”. I’ll provide a direct answer… and a more meaningful answer. Imagine that you have a list of data blocks with some metadata for each block that tells…

Part 8 – How Hadooped is SQL Server PDW with Polybase?

Now for SQL Server… continuing the thread on RDBMS-Hadoop integration (Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7) I have suggested that we could evaluate integration architecture using three criteria: How parallel are the pipes to move data between the RDBMS and the parallel file system; Is there intelligence to push down predicates; and Is…

Part 6: How Hadooped is HANA?

Now for HANA plus Hadoop… to continue this thread on RDBMS-Hadoop integration (Part 1, Part 2, Part 3, Part 4, Part 5) I have suggested that we could evaluate integration architecture using three criteria: How parallel are the pipes to move data between the RDBMS and the parallel file system; Is there intelligence to push…