In-database analytics options (Greenplum-specific)
This section covers advanced SQL techniques for in-database analytics within Greenplum.
The following techniques will be discussed in detail:
- Windows functions
- User-defined functions and aggregates
Window functions
Window functions are a new class of functions introduced in Greenplum. The WINDOW clause is used to define a window that can be used in the OVER() expression of a window function such as rank or avg. For information on OLAP extensions and window functions refer to the Greenplum Database Reference guide. Window functions allow application developers to more easily compose complex OLAP queries using standard SQL commands. For example:
- Moving averages or sums can be calculated over various intervals. ...
Get Getting Started with Greenplum for Big Data Analytics now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
