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LI-T188.8.131.52889 Firebird 3.0 Alpha 2
b as (
select 0 rc
from rdb$database qa
join rdb$database q1 on q1.rdb$relation_id*0=b.rc*0
join rdb$database q2 on q2.rdb$relation_id*0=b.rc*0
select * from b
Result: "Column does not belong to referenced table." (seems that it is 'b.rc' column that is source of trouble).
Same query in LI-V184.108.40.206744 Firebird 2.5 runs OK and return two rows (0 and 1).
The problem disappears if second join: "join rdb$database q2 on q2.rdb$relation_id*0=b.rc*0" - is commented out.