group by zuozhebianhao having count(*)>=3
问题描述:
group by zuozhebianhao having count(*)>=3
答
group by zuozhebianhao 是以zuozhebianhao 分组.
having 相对于where,是过滤的一种,不同的是在分组后做条件过滤.
count(*)>=3 是分组后累计行数大于等于3.