Busybox for Android v1.20.2 Stable built by Linus Yang [Aug 12, 2012 Update] - Update to 1.20.2 stable [Features] - Tested on Android 2.1, 2.3, 4.0 and 4.1. Should be capable with all Android devices (Use at your own risk) - ELF armv5te binary (stat
Given a specified total t and a list of n integers, find all distinct sums using numbers from the list that add up to t. For example, if t=4, n=6, and the list is [4,3,2,2,1,1], then there are four different sums that equal 4: 4,3+1,2+2, and 2+1+1.(
Fuji POD UG series(GENERAL-PURPOSE SERIAL COMMUNICATION)(2)pdf,Fuji POD UG series(GENERAL-PURPOSE SERIAL COMMUNICATION)(2)Record of revisions
Printing date
Reference no
Revised contents
Juy,1999
FEH353
1st Edition printed
December. 2002
FEH353a
2nd E
Oracle中的SUM条件查询
1、按照区域编码分组查询区域编码、IPTV_NBR不为空的数量、ACC_NBR不为空的数量、所有用户数量
SELECT
AREA_CODE,
SUM (
CASE
WHEN IPTV_NBR IS NULL or IPTV_NBR = '' THEN
0
ELSE
1
END
),
SUM (
CASE
WHEN ACC_NBR IS NULL or ACC_NBR = '' THEN
0
ELSE
1
END
),
COUNT (*)
FROM
GAT_SQM
查看表空间的名称及大小 代码如下: SQL>select t.tablespace_name, round(sum(bytes/(1024*1024)),0) ts_size from dba_tablespaces t, dba_data_files d where t.tablespace_name = d.tablespace_name group by t.tablespace_name; 查看表空间物理文件的名称及大小: 代码如下: SQL>select tablesp
SUM是对符合条件的记录的数值列求和
COUNT 是对查询中符合条件的结果(或记录)的个数
例如:
表fruit
id name price
1 apple 3.00
2 pear 4.00
select count(price) from fruit; —-执行之后结果为:2 (表示有2条记录)
select sum(price) from fruit;—执行之后结果为:7:00(表示各记录price字段之和为7.00)
比如user_num表:
例1:查询出现过2次的user
往往初学者会错误地认为在where 语句里直接使用count()算法,很显然这个想法是错误的,count()方法并不能被用在where子句中,为了解决问题,我们可以在group by子句后面使用HAVING来做条件限制。错误做法:select * from user_num where count(user)>=2 group by user;正确做法:select * from user_num group by user HAV