Updated on 2023-10-23 GMT+08:00

PGXC_NODE

The PGXC_NODE system catalog stores information about database instance nodes. This system catalog has specific meanings only in distributed scenarios. Centralized systems can query only the table definition.

Table 1 PGXC_NODE columns

Name

Type

Description

oid

oid

Row identifier (hidden attribute, which must be specified)

node_name

name

Node name

node_type

"char"

Node type
  • C: CN
  • D: DN
  • S: standby node

node_port

integer

Port number of the node

node_host

name

Host name or IP address of a node. (If a virtual IP address is configured, its value is a virtual IP address.)

node_port1

integer

Port number of a replication node

node_host1

name

Host name or IP address of a replication node. (If a virtual IP address is configured, its value is a virtual IP address.)

hostis_primary

boolean

Whether a primary/standby switchover occurs on the current node

  • t (true): yes
  • f (false): no

nodeis_primary

boolean

Whether the current node is preferred to execute non-query operations in the replication table

  • t (true): yes
  • f (false): no

nodeis_preferred

boolean

Whether the current node is preferred to execute queries in the replication table

  • t (true): yes
  • f (false): no

node_id

integer

Node identifier. The value is obtain by calculating the value of node_name using the hash function.

sctp_port

integer

Port used by the TCP proxy communication library or SCTP communication library of the primary node to listen on the data channel. (Due to specification changes, the current version no longer supports the current feature. Do not use this feature.)

control_port

integer

Port used by the TCP proxy communications library of the primary node to listen on the control channel

sctp_port1

integer

Port used by the TCP proxy communication library or SCTP communication library (Due to specification changes, the current version no longer supports the current feature. Do not use this feature.) of the standby node to listen on the data channel

control_port1

integer

Port used by the TCP proxy communications library of the standby node to listen on the control channel

nodeis_central

boolean

Whether the current node is a CN. It is invalid for DNs.

  • t (true): yes
  • f (false): no

nodeis_active

boolean

Whether the current node is normal. It is invalid for DNs.

  • t (true): yes
  • f (false): no