我不知道/分组依据？有？子查询？我能用什么？
I don't know / group by ? having ? subquery? what can I use?
select seq from a where link != 1
seq | link
1 | 1
1 | 0
2 | 0
3 | 1
4 | 0
我想要 return 序列不在 1 : 2, 4
SELECT seq
FROM a
GROUP BY seq
HAVING SUM(link = 1) = 0;
select seq from a where link != 1
seq | link
1 | 1
1 | 0
2 | 0
3 | 1
4 | 0
我想要 return 序列不在 1 : 2, 4
SELECT seq
FROM a
GROUP BY seq
HAVING SUM(link = 1) = 0;