找到连续的数子

table1 中 找出连续出现三次的数

id num

1 1

2 1

3 1

4 2

5 1

6 1

7 2

select

distinct num

from(

select

num,

lag(num,1,null) over (order by id asc) as num1,

lag(num,2,null) over (order by id asc) as num2,

from table1

) t1 where num = num1 and num1 = num2