MySQL取并集去掉交集怎么写

select * from table1 t where t.a>10 or t.b>20

and id not in (select id from table1 m where m.a>20 and m.b>20)

select A.id,A.aaa,A.bbb,B.ccc,B.ddd

from A left join B

on A.id=B.id

union

select B.id,A.aaa,A.bbb,B.ccc,B.ddd

from A right join B

on A.id=B.id

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