No tables show in the dropdown:

All the tables should be listed in the Reference table box for me to select.
I suppose you are the first one reorting that issue for PostgreSQL. And I think the feature was not well tested by myself on PostgreSQL. So let's get foreign keys to work on PostgreSQL.
Yep, that was me.
Also already created foreign keys do not show up on postgres. Using postgres 11.5.3
The bug is still present with
Version 10.3.0.5837 (64 Bit)
Compiled on: 2020-01-19 19:55:50
Could you please check with the latest build (5848 currently)
Reference table does not populate and created foreign keys do not show. Build 5849. psql (PostgreSQL) 12.1 (Debian 12.1-1.pgdg100+1)
What would be a good SQL approach to retrieve foreign keys of one table? I know I can join pg_index with pg_class to get many index details, but for HeidiSQL that query should deliver also the reference table and columns from source and reference table:
SELECT * FROM pg_index i, pg_class c
WHERE
i.indexrelid=c.oid
I found this on Stack overflow
SELECT
tc.table_schema,
tc.constraint_name,
tc.table_name,
kcu.column_name,
ccu.table_schema AS foreign_table_schema,
ccu.table_name AS foreign_table_name,
ccu.column_name AS foreign_column_name
FROM
information_schema.table_constraints AS tc
JOIN information_schema.key_column_usage AS kcu
ON tc.constraint_name = kcu.constraint_name
AND tc.table_schema = kcu.table_schema
JOIN information_schema.constraint_column_usage AS ccu
ON ccu.constraint_name = tc.constraint_name
AND ccu.table_schema = tc.table_schema
WHERE tc.constraint_type = 'FOREIGN KEY' AND tc.table_name='truck_setups_workers';
"table_schema" "constraint_name" "table_name" "column_name" "foreign_table_schema" "foreign_table_name" "foreign_column_name"
"public" "fk_rails_d00006069d" "truck_setups_workers" "truck_setup_id" "public" "truck_setups" "id"
"public" "fk_rails_a1cce43842" "truck_setups_workers" "employee_id" "public" "employees" "id"
In 5850 it looks like the reference tables are now populating.
In 5850 it looks like the reference tables are now populating.
Really, in PostgreSQL? Or on MySQL or MS SQL?
PostgreSQL

Just tested 5771 and it definitely doesn't populate there.
Oh yes, I was mixing this issue with #158 , which complains about non working detection of foreign keys. This one is just for the reference tables, which I fixed in conjunction with 7ab47a31434cda49e14604d7b2d2b1e79c89b5aa for #150 .
Thanks for your feedback!