The gp_pgdatabase view shows status information about the Greenplum segment instances and whether they are acting as the mirror or the primary. This view is used internally by the Greenplum fault detection and recovery utilities to determine failed segments.

Table 1. pg_catalog.gp_pgdatabase
column type references description
dbid smallint gp_segment_configuration.dbid System-assigned ID. The unique identifier of a segment (or master) instance.
isprimary boolean gp_segment_configuration.role Whether or not this instance is active. Is it currently acting as the primary segment (as opposed to the mirror).
content smallint gp_segment_ configuration.content The ID for the portion of data on an instance. A primary segment instance and its mirror will have the same content ID.

For a segment the value is from 0-N, where N is the number of segments in Greenplum Database.

For the master, the value is -1.

definedprimary boolean gp_segment_ configuration.preferred_role Whether or not this instance was defined as the primary (as opposed to the mirror) at the time the system was initialized.