您可以简单地使用NOT EXISTS：

select * from table_a ta
where not exists (select * from table_b tb
                  where tb.field_1 = ta.field_1
                    and tb.field_2 = ta.field_2)

使用不存在：

select * from table_A where not exists (select * from table_B 
                  where table_B.field_1 = table_A.field_1
                    and  table_B.field_2 = ta.field_2)

可以使用反联接。例如：

select *
from table_a a
left join table_b b on b.field_1 = a.field_1 and b.field_2 = a.field_2
where b.field_1 is null