The RUN_LOAD_BALANCE_POLICY function returns a string formatted as address:port that results from running the current Native Load Balancer policy.
It’s a great tool for testing after enabling a new Load Balance Policy!
Example:
dbadmin=> SELECT set_load_balance_policy('ROUNDROBIN');
set_load_balance_policy
--------------------------------------------------------------------------------
Successfully changed the client initiator load balancing policy to: roundrobin
(1 row)
dbadmin=> SELECT node_name, node_address FROM nodes;
node_name | node_address
--------------------+---------------
v_test_db_node0001 | 172.16.61.176
v_test_db_node0002 | 172.16.61.177
v_test_db_node0003 | 172.16.61.178
(3 rows)
dbadmin=> SELECT local_node_name();
local_node_name
--------------------
v_test_db_node0001
(1 row)
dbadmin=> SELECT run_load_balance_policy();
run_load_balance_policy
-------------------------
172.16.61.176:5433
(1 row)
dbadmin=> SELECT run_load_balance_policy();
run_load_balance_policy
-------------------------
172.16.61.177:5433
(1 row)
dbadmin=> SELECT run_load_balance_policy();
run_load_balance_policy
-------------------------
172.16.61.178:5433
(1 row)
dbadmin=> SELECT local_node_name();
local_node_name
--------------------
v_test_db_node0001
(1 row)
Because the local node did not change in the above example, note that running the RUN_LOAD_BALANCE_POLICY functions does not actually redirect the session to the node returned by the function.Helpful Links: https://www.vertica.com/docs/latest/HTML/Content/Authoring/AdministratorsGuide/ManagingClientConnections/LoadBalancing/ConnectionLoadBalancing.htm https://www.vertica.com/docs/latest/HTML/Content/Authoring/SQLReferenceManual/Functions/VerticaFunctions/ConnectionManagement/SET_LOAD_BALANCE_POLICY.htm
Have fun!
About the Author
James Knicely
Vertica Field Chief Technologist
I've had the privilege of working with many database technologies in my career. But after being introduced to Vertica in May of 2011 as a client, I was hooked on the new technology after witnessing a query run in milliseconds that had previously ran for hours on the legacy database we had in place. It was then that I knew I wanted to eventually join the Vertica team, and 4 years later I did! I am currently a Vertica evangelist and am ready to help you get on board! Please feel free to reach out to me with any questions you have about Vertica and make sure to follow my Vertica Quick Tips!
