數據中，a=3的時候，不要c=2的數據；a=1的時候，不要c=3的數據
SELECT t1.a, t1.c
FROM guofengds t1
WHERE NOT EXISTS (select t.a, t.c
from table t
WHERE a = t1.a
AND a = 3
AND c = t1.c
AND c = 2)
AND NOT EXISTS (select t.a, t.c
from table t
WHERE a = t1.a
AND a = 1
AND c = t1.c
AND c = 3)