昨晚看的书,发现可以用T-SQL 实现自定义递归,其实也就是变相的 foreach 直接上代码 ,不懂得可问: ),col int ) -- id 增量id pid该数据的上级增量id name 名称 declare @id int ,@col int insert into @t select id,pid,[name],@col from dbo.CTE where id=@id begin insert into @t select CTE.id,CTE.pid,CTE.[name],@c
CTE是如何进行递归的?产生递归的条件有三个,分别是 初始值 自身调用自身 结束递归的条件 1,示例代码 ;with cte as ( as jd union all as jd from cte ) select * from cte 查询结果如下 2,递归过程分析 2.1 初始值 select 1 as id, 1 as jd 提供初始值,CTE中的值只有这一个. 2.2 第一次递归调用 select id +1 as id ,jd+2 as jdfrom ctewhere id<10 在第
A procedure body can contain calls to other procedures, not least itself: (define factorial (lambda (n) (if (= n 0) 1 (* n (factorial (- n 1)))))) This recursive procedure calculates the factorial of a number. If the number is 0, the answer is 1. For
You are climbing a stair case. It takes n steps to reach to the top. Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top? Note: Given n will be a positive integer. 题目分析:每次只能走1或2步,问n步的话有多少中走法???? 可以用动态规划和递归解