select * from geimstatus_history twhere to_date(t.data_time,'YYYY-mm-dd') = to_date(sysdate,'YYYY-mm-dd') AND t.car_state='11' order by t.gei_mes desc, t.data_time desc
转自:http://bbs.csdn.net/topics/370033478 对于Oracle中分页排序查询语句执行效率的比较分析 作者:lzgame 在工作中我们经常遇到需要在Oracle中进行分页.排序.查询的组合SQL语句,举例来说,通常我们会这样写:(假定表test中id是主键,并且id从1开始没有间断顺序排列) 1. SELECT * FROM ( SELECT id,a1,a2,a3,a4,a5,a6,a7,a8,a9, ROWNUM AS rn FROM test
ORACLE可以借助DECODE函数,自定义顺序排序: select * from ( select 'Nick' as item from dual union all select 'Viki' as item from dual union all select 'Glen' as item from dual union all select 'Robin' as item from dual union all select 'Total' as item from dual ) pr
项目开发中,我们有时会碰到需要分组排序来解决问题的情况,如:1.要求取出按field1分组后,并在每组中按照field2排序:2.亦或更加要求取出1中已经分组排序好的前多少行的数据 这里通过一张表的示例和SQL语句阐述下oracle数据库中用于分组排序函数的用法. a.row_number() over() row_number()over(partition by col1 order by col2)表示根据col1分组,在分组内部根据col2排序,而此函数计算的值就表示每组内部排序后的顺序
在oracle中使用union all或者 union 对两个结果集进行并集操作时,如果需要对查询结果集进行排序时,不能直接在后面加order by + 表字段 来排序 例如: 在oracle的soctt用户中emp表对部门号为20和30的员工进行并集操作: SQL> select * from emp where deptno = 20 union all select * from emp where deptno =30 ; EMPNO ENAME JOB MGR HIREDATE SAL
参考资料: http://docs.oracle.com/database/122/SQLRF/ROWNUM-Pseudocolumn.htm#SQLRF00255 http://blog.csdn.net/u010395242/article/details/52047341 在采用以下所示的方式: SELECT * FROM (SELECT row_.*, rownum rownum_ FROM (SELECT * FROM table_name ORDER BY table_name.cr
ORACLE可以借助DECODE函数,自定义顺序排序: select * from ( select 'Nick' as item from dual union all select 'Viki' as item from dual union all select 'Glen' as item from dual union all select 'Robin' as item from dual union all select 'Total' as item from dual ) pr
例子: 一个字符串"11,15,13,17,12",以逗号分割,现在要排序成"11,12,13,15,17". 写了一个实现方法,记录下来以备后用: -------------------------------------------------------- -- Export file for user BEN -- -- Created by Administrator on 2015/8/5 星期三, 10:24:20 -- ---------------
第二章:排序.限制查询行 一.order by子句 1.order by排序规则 (1)asc,升序排列,默认取值 (2)desc,降序排列 (3)order by是select命令的最后一个子句 select last_name,salary,dept_id from s_emp order by salary; select last_name,salary,dept_id from s_emp order by salary asc; select last_name,salary,dep
Syntax ORDER BY { column-Name | ColumnPosition | Expression } [ ASC | DESC ] [ NULLS FIRST | NULLS LAST ] [ , column-Name | ColumnPosition | Expression [ ASC | DESC ] [ NULLS FIRST | NULLS LAST ] ] * 知识点 order by 后面可以接列号(数字).列名.别名.表达式.函数.分组函数 order b
需求: 查询每个供应商在每个类型产品销售的top50中有多少 分析: 1.查询,以指定字段(供应商.产品类型)分组,取每个分组的前50行,查看每个供应商的数量 2.使用rank函数给每个供应商.每个类型产品的销售量做个排名,添加伪劣ran 3.筛选ran小于等于50的行,以供应商.产品类型分组,count sql: ) num from (select t.gyscode, t.typeid, sum(t.sale) sale, rank() over(partition by t.gyscod
因项目需求,需要将查询结果,去重后,在按照主键(自增列)排序,百度一番,记录下来 DEMO SELECT * FROM (SELECT ROW_NUMBER() OVER(PARTITION BY STATION_NAME ORDER BY ID DESC) RNO,STATION_NAME,ID FROM EMES_MAC) WHERE RNO= ORDER BY ID DESC 格式:SELECT * FROM (SELECT ROW_NUMBER() OVER(PARTITION BY 去
SQL排序查询 DESC降序.ASC升序(默认是升序) /* 语法结构: SELECT * | 列名1[,列名2...] | 表达式 FROM 表名 [WHERE 限定条件] ORDER BY 列名1 ASC | DESC,列名2 ASC | DESC; */ --查询员工信息,对部门编号进行降序排序 SELECT * FROM EMP E ORDER BY E.DEPTNO DESC; --查询30号部门的员工信息,对薪资尽心升序排序 SELECT * FROM EMP E WHERE E.D