how to structure queries like SELECT a.col IN ( b.col FROM b ) FROM a ?

hi monetdb team, i've pasted a minimal reproducible example of a few SQL queries that i had expected to work -- only about half of them do work, and the other half just error with 'ParseException:SQLparser:' my goal is to get the very last line working, so if anybody could suggest a hack or a workaround that doesn't involve a JOIN, i would appreciate it. thanks all!! CREATE TABLE table_one (this_column INTEGER) ; INSERT INTO table_one VALUES (1) ; INSERT INTO table_one VALUES (2) ; INSERT INTO table_one VALUES (3) ; INSERT INTO table_one VALUES (4) ; INSERT INTO table_one VALUES (5) ; CREATE TABLE table_two (this_column INTEGER) ; INSERT INTO table_two VALUES (1) ; INSERT INTO table_two VALUES (2) ; # works as expected SELECT SUM( ( table_one.this_column IN ( SELECT this_column FROM table_two ) ) ) FROM table_one ; SELECT MAX( ( table_one.this_column IN ( SELECT this_column FROM table_two ) ) ) FROM table_one ; # fails SELECT ( table_one.this_column IN ( SELECT this_column FROM table_two ) ) AS new_column FROM table_one ; # Server says 'ParseException:SQLparser:'. # works SELECT AVG( CASE WHEN table_one.this_column IN ( SELECT this_column FROM table_two ) THEN 1 ELSE 0 END ) AS new_column FROM table_one ; # fails SELECT ( CASE WHEN ( table_one.this_column IN ( SELECT this_column FROM table_two ) ) THEN 1 ELSE 0 END ) AS new_column FROM table_one ; # Server says 'ParseException:SQLparser:'. # fails [[this query is the one i would like to implement]] SELECT COUNT(*) , ( CASE WHEN ( table_one.this_column IN ( SELECT this_column FROM table_two ) ) THEN 1 ELSE 0 END ) AS new_column FROM table_one GROUP BY new_column ; # Server says 'ParseException:SQLparser:'.