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Date: Tue, 21 Oct 2025 10:31:40 -0600
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From: Sbob <sbob@quadratum-braccas.com>
Subject: FDW/Foriegn Table pointing to pgpool never gets load balanced
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All;


I setup a Foreign Server pointing to a pgpool instance. Subsequently 
created Foreign Tables work as expected but they are never load 
balanced, it seems they always run on the first available node. My 
latest test used a pgpool config pointing to 2 standby's (no master) and 
set both backend nodes to DISALLOW failovers

I have load balancing configured and I have statement_level_load_balance 
= on

I set log_min_duration_statement to 0 on both backend nodes and ran 
several selects from the local Foreign table, I see this in the logfile 
from data node 0:


2025-10-21 08:52:53.876 MDT [58156] LOG:  duration: 0.032 ms statement: 
START TRANSACTION ISOLATION LEVEL REPEATABLE READ
2025-10-21 08:52:53.877 MDT [58156] LOG:  duration: 0.063 ms parse 
<unnamed>: DECLARE c1 CURSOR FOR
         SELECT id FROM public.abc WHERE ((id < 15))
2025-10-21 08:52:53.877 MDT [58156] LOG:  duration: 0.006 ms  bind 
<unnamed>: DECLARE c1 CURSOR FOR
         SELECT id FROM public.abc WHERE ((id < 15))
2025-10-21 08:52:53.877 MDT [58156] LOG:  duration: 0.043 ms execute 
<unnamed>: DECLARE c1 CURSOR FOR
         SELECT id FROM public.abc WHERE ((id < 15))
2025-10-21 08:52:53.878 MDT [58156] LOG:  duration: 0.043 ms statement: 
FETCH 100 FROM c1
2025-10-21 08:52:53.878 MDT [58156] LOG:  duration: 0.005 ms statement: 
CLOSE c1
2025-10-21 08:52:53.878 MDT [58156] LOG:  duration: 0.016 ms statement: 
COMMIT TRANSACTION


And I see this in the logfile from data node 1:


2025-10-21 08:52:27.675 MDT [58138] LOG:  duration: 0.026 ms statement: 
START TRANSACTION ISOLATION LEVEL REPEATABLE READ
2025-10-21 08:52:27.676 MDT [58138] LOG:  duration: 0.020 ms statement: 
COMMIT TRANSACTION


No matter how many selects I run from the Foreign Table I see the same 
entries in the data node postgres log files and it never load balances 
the queries from the Foreign Table


Anyone have any Ideas how to get this to load balance?


Thanks in advance