所有版本的oracle都可以使用select wm_concat(name) as name from user; 但如果是oracle11g,使用select listagg(name, ',') within group( order by name) as name from user;效率更高,官方也更推荐这种写法.
group by rollup() 按分组合计 select grouping(status),status,owner,object_type,count(*) from dba_objects where owner not in ('SYS','SYSTEM') group by rollup (status,owner,object_type) order by status,owner,object_type; 经典分类查询语句: select object_type,count(*)
//DataTable以列分组 var result = from r in dt.AsEnumerable() group r by ), b = r.Field<) } into g select new { key = g.Key, count = g.Count() }; var s = result.ToList();
oracle 行转列 首先看一下源数据: 方法一:WM_CONCAT group by 这个方法没有问题. SELECT CODE_TS, WMSYS.WM_CONCAT(S_NUM + || ':' || ELEMENT) ELEMENT FROM T_MERCH_ELEMENT ' group by CODE_TS; 得到的结果: 上面大家可能会发现序号没有按顺序排列下来.如果没有要求,就这样就可以了.如果要排序看方法二. 方法二:WM_CONCAT OVER 有特殊数据时会报错.报:“操
Oracle中对列加密的方法 2011-12-22 17:21:13 分类: Linux Oracle支持多种列加密方式: 1,透明数据加密(TDE):create table encrypt_col(id int,txt varchar2(100) encrypt using '算法名称' identified by '密钥' no salt);优点:对应用完全透明缺点:需要数据库管理员管理wallet,增加了管理复杂性,也无法避免数据库管理员查看原文. 2,使用DBMS_CRYPTO包优点:
1. Oracle自带列转行函数listagg: 实例: with temp as( select 'China' nation ,'Guangzhou' city from dual union all select 'China' nation ,'Shanghai' city from dual union all select 'China' nation ,'Beijing' city from dual union all select 'USA' nation ,'New York
Oracle增加一列.修改一列数据类型: 添加一列: alter table A add( CFYJSNR varchar2(20)); 修改列: alter table A rename column CFYJSNR to CFJYSNR; 修改列的类型: alter table A modify cfyj varchar(200); 删除数据库一列 alter table A drop column CFYJSNR 使用心得,当使用plsql执行的时候,注意
来源:https://codedefault.com/2018/group-by-multiple-columns-and-sum-in-csharp .NET[C#]LINQ按多列分组(Group By)并计算总和(Sum) SQL语句: SELECT * FROM <TableName> GROUP BY <Column1>,<Column2> QuantityBreakdown ( MaterialID int, ProductID int, Quantity f
DB2通过某列分组来去重,可防止distinct对大字段的去重报错. 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编号(组内连续的唯一的) SELECT *, Row_Number() OVER (partition by deptid ORDER BY salary desc) as aa rank FROM employee WHERE
--测试数据create table rowtocol_test asselect 2009 year,1 month,'部门1' dept,50000 expenditure from dualunion all select 2009,2,'部门1',20000 from dualunion all select 2009,2,'部门1',30000 from dualunion all select 2010,1,'部门1',35000 from dualunion all select
