where vs having当一个sql语句中存在where子句,会先执行where,然后执行group by,然后执行having.一般来说,only use 'having' when you use 'group by'Always use 'having' with aggregate f...
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其他好文 时间:
2014-07-07 16:58:32
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183
题目链接:uva 1069 - Always an integer
题目大意:给出一个多次多项式,问说是否对于任意正整数n来说结构均为整数。
解题思路:首先处理出字符串,然后枚举n从1到k+1判断即可,k为多项式中出现过的最大幂数指。
P为多项式,d为除数,k为多项式中最大的次数
当k=0时,P中不存在n变量,所以直接计算判断即可当k=1时,P是一次多项式,那么P(n+...
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其他好文 时间:
2014-07-02 09:45:48
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294
1069 - Always an integer...
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其他好文 时间:
2014-07-02 08:12:34
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198
It always seems that your vacuum will malfunction right before company is set to arrive. What do you do if your vacuum is not working correctly? Many ...
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其他好文 时间:
2014-07-01 22:38:53
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305
linux 基本命令ls (list 显示当前目录下文件和目录 ls -l 详细显示 =ll )[root@linux ~]# ls [-aAdfFhilRS] 目录名称[root@linux ~]# ls [--color={none,auto,always}] 目录名称[root@linux ~...
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系统相关 时间:
2014-06-30 22:44:24
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461
Before I owned a pool I always thought that pool maintenance was going to be a real pain and troublesome. I had heard many horror stories from friends...
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其他好文 时间:
2014-06-30 21:58:20
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316
题目地址:https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1269
Jamie is a very popular girl and has quite a lot of friends, so she always keeps a v...
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其他好文 时间:
2014-06-30 16:55:26
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374
【题目】
Design and implement a data structure for Least Recently Used (LRU) cache. It should support the following operations: get and set.
get(key) - Get the value (will always be positive) of the key if the key exists in the cache, otherwise return -1.
se...
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其他好文 时间:
2014-06-29 22:45:26
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358
Add include to "freetype.h"/* add this line */#include #ifndef FT_FREETYPE_H#error "`ft2build.h' hasn't been included yet!"#error "Please always use m...
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其他好文 时间:
2014-06-29 20:24:58
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312
DescriptionFor the daily milking, Farmer John'sNcows (1 ≤N≤ 50,000) always line up in the same order. One day Farmer John decides to organize a game o...
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其他好文 时间:
2014-06-28 09:32:17
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200