O'Reilly logo

Greenplum - Architecture and SQL by Leona Coffing, Tom Coffing

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Chapter 22 – Table Create and Data Types

“Create a definite plan for carrying out your desire and begin at once, whether you are ready or not, to put this plan into action. “

- Napoleon Hill

Greenplum Has Only Two Distribution Policies

Greenplum has two ways to distribute a table:

1)Hash Distribution

2)Round Robin Distribution

Most Greenplum tables will use a Hash distribution. A column(s) arechosen at the distribution key. This column(s) is run through theGreenplum hashing algorithm to divide data among all of thesegments. Like values will hash to the same segment.

The biggest performance advantage comes when two tables arejoined. If both tables use the Distribution Key as the Join Key thenthe join will happen ”Segment Local”. Greenplum does ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required