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HomeDatabaseMysql TutorialOracle 按时间段分组统计

select (sysdate-13)-(level-1)/4 from dual connect by levellt;=34 --从第一条时间记录开始(sysdate-13)为表中的最早的日期

想要按时间段分组查询,首先要了解level,connect by,Oracle时间的加减.
关于level这里不多说,我只写出一个查询语句:

---level 是一个伪例 select level from dual connect by level 关于connect by可以看

Oracle时间的加减看看试一下以下sql语句就会知道:

select sysdate -1 from dual ----结果减一天,也就24小时 select sysdate-(1/2) from dual -----结果减去半天,也就12小时 select sysdate-(1/24) from dual -----结果减去1 小时 select sysdate-((1/24)/12) from dual ----结果减去5分钟 select sydate-(level-1) from dual connect by level下面是本次例子: select dt, count(satisfy_degree) as num from T_DEMO i , (select sysdate - (level-1) * 2 dt from dual connect by level d.dt-2 group by d.dt


例子中的sysdate - (level-1) * 2得到的是一个间隔是2天的时间
group by d.dt  也就是两天的时间间隔分组查询

自己实现例子:

create table A_HY_LOCATE1
(
  MOBILE_NO          VARCHAR2(32),
  LOCATE_TYPE        NUMBER(4),
  AREA_NO            VARCHAR2(32),
  CREATED_TIME       DATE,
  AREA_NAME          VARCHAR2(512),
);

select (sysdate-13)-(level-1)/4 from dual connect by level

一下是按照每6个小时分组  
select mobile_no,area_name,max(created_time ),dt, count(*) as num from a_hy_locate1  i ,
(select (sysdate-13)-(level-1)/4  dt
from dual connect by level where i.locate_type = 1 and
i.created_time

d.dt-1/4
group by mobile_no,area_name,d.dt

linux

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