Glossary

Specify the number of replicas of the data that should exist in the database. The K safety sets the fault tolerance for the Vertica cluster, where K can be set as 0 or 1. Specify a value based on the number of nodes in the cluster, which is measured as 2k+1. For example: the K factor 0 is ideal for a single node cluster. If the K factor is 1, then you need to have a minimum of 3 nodes. Vertica recommends a K-safety value of 1.

K-factor also determines the number of identical instance of the segmented projections to be created for fail safety. Vertica stores table data in projections that are a collection of table columns, which optimizes query execution. The projection data can be divided into multiple segments or can be maintained as a single unsegmented unit. To ensure high availability of data, unsegmented projections are replicated on all the nodes and a segmented projection should have K+1 identical instances (buddies). For example: if the K- factor is specified as 1, then 2 identical instances of the segment are maintained.

The unit of time used by ZooKeeper that is translated to milliseconds. All time-dependent operations for ZooKeeper are based on tick time.