I've setup foreign table and noticed inconsistency how conditionals handled for boolean columns.
explain verbose select * from temporary_testing.t_proxied where active is true; QUERY PLAN -------------------------------------------------------------------------------------- Foreign Scan on temporary_testing.t_proxied (cost=100.00..194.72 rows=1412 width=5) Output: id, active Filter: (t_proxied.active IS TRUE) Remote SQL: SELECT id, active FROM main_testing.t_url
But, when = used instead of IS it works correctly. All conditions below (including IS NULL) are pushed down to remote server:
explain verbose select * from temporary_testing.t_proxied where active; explain verbose select * from temporary_testing.t_proxied where NOT(active); explain verbose select * from temporary_testing.t_proxied where active = false; explain verbose select * from temporary_testing.t_proxied where active = true;
-------------------------------------------------------------------------------------- Foreign Scan on temporary_testing.t_proxied (cost=100.00..166.48 rows=1412 width=5) Output: id, active Remote SQL: SELECT id, active FROM main_testing.t_url WHERE (active)
explain verbose select * from temporary_testing.t_proxied where active is null; QUERY PLAN ------------------------------------------------------------------------------------ Foreign Scan on temporary_testing.t_proxied (cost=100.00..138.52 rows=14 width=5) Output: id, active Remote SQL: SELECT id, active FROM main_testing.t_url WHERE ((active IS NULL))
