LEVEL, SYS_CONNECT_BY_PATH(last_name,'/') "Path"FROMemployeesWHERElevel<=3ANDdepartment_id=80STARTWITHlast_name='King'CONNECTBYPRIOR employee_id=manager_idANDLEVEL<=4; ERROR: ORA-01436:CONNECTBYloopinuserdata CONNECT BY 条件中的 NOCYCLE 参数使 Oracle 尽管有循环仍返回行。 CONNECT_BY_ISCYCLE ...
6、CONNECT_BY_ROOT的使用,oracle10g新增connect_by_root,用在列名之前表示此行的根节点的相同列名的值。 1SELECTLEVELAS等级,2CONNECT_BY_ISLEAFAS是否是叶子节点,3CONNECT_BY_ROOT ENAME,4LPAD('',LEVEL*2-1)||SYS_CONNECT_BY_PATH(ENAME,'=>'),5E.*6FROMEMP E7CONNECTBYPRIOR E.EMPNO=E.MGR8STARTWI...
6、CONNECT_BY_ROOT的使用,oracle10g新增connect_by_root,用在列名之前表示此行的根节点的相同列名的值。 1SELECTLEVELAS等级,2CONNECT_BY_ISLEAFAS是否是叶子节点,3CONNECT_BY_ROOTENAME,4LPAD(' ',LEVEL*2-1)||SYS_CONNECT_BY_PATH(ENAME,'=>'),5E.*6FROMEMPE7CONNECTBYPRIORE.EMPNO=E.MGR8STARTWITHE....
ConnectBy、Level、StartWith的使用 ConnectBy、Level、StartWith的使⽤ORACLE--Connect By、Level、Start With的使⽤(Hierarchical query-层次查询)Syntax 1CONNECT BY [NOCYCLE] <condition> START WITH <condition> Syntax 2START WITH <condition> CONNECT BY [NOCYCLE] <condition> 参考⽹址:http://asktom....
2、查看每个等级的人数。主要是通过LEVEL进行GROUP BY 1SELECTCOUNT(LEVEL)2FROMEMP E3CONNECTBYPRIOR E.EMPNO=E.MGR4STARTWITHE.MGRISNULL5GROUPBYLEVEL; 3、Oracle 10g提供了一个简单的connect_by_isleaf=1, 0 表示非叶子节点 1SELECTLEVELAS等级, CONNECT_BY_ISLEAFAS是否是叶子节点, E.*2FROMEMP E3CONNECT...
三、start with ... connect by 用法讲解: 构建如下table: ID NAME PID 1 10 0 2 11 1 3 20 0 4 12 1 5 121 2 code example1: select TBL_TEST.*, level from TBL_TEST start with pid= 1 -- 可写到 connect by 后面 connect by prior pid = id ...
"start with" -- this identifies all level=1 nodes in the tree "connect by" -- describes how to walk from the parent nodes above to their children and their childrens children. Easiest to use an example on emp. if we start with "where mgr is null", we generate the set of employees...
oracle 进阶 connect by 和level 的用法 Oracle中start with…connect by prior子句用法 connect by 是结构化查询中用到的,其基本语法是: 例: 简单说来是将一个树状结构存储在一张表里,比如一个表中存在两个字段:org_id,parent_id,那么通过表示每一条记录的parent是谁,就可以形成一个树状结构,用上述语法的查...
withEtag public OpenIdConnectProvidersCreateOrUpdateHeaders withEtag(String etag) Set the etag property: The Etag property. Parameters: etag - the etag value to set. Returns: the OpenIdConnectProvidersCreateOrUpdateHeaders object itself.Applies to Azure SDK for Java Late...
Python中的循环 while循环 for循环 While循环和for循环 While expression: #expression是表达式 当expression值为true的时候执行代码块 Suite_to_repeat #代码块必须缩进 -python的while可以用else For iter_var in iterab...Oracle 层级查询 Connect By 层级查询 Oracle 的层级查询原理类似于递归。所以有时也称之...