cubrid的中sql查询语法Hierarchical QuerySQL层级查询 官方文档是英文的,看不明白可以参看ocracle的同类函数说明.很多都是一样的. ORACLE中CONNECT BY...START WITH 和ocracle的差不多 ,下面的说明就直接抄袭过来 http://www
-- In a hierarchical query, do not specify either ORDER BY or GROUP BY, -- as they will destroy the hierarchical order of the CONNECT BY results. DEPT_ID PARENT_ID DEPT_NAME AMOUNT --- --- --- --- 1 1 2 7 3 1-3-7 5 8 3 1-3-8 6 3 1 1-3 8 5 2 1-2-5 9 4 2...
自连接经常被用来查询分层数据(hierarchical data)或将一条记录与同一表中的其他记录进行比较。 一个最简单的例子——找到和10293号订单同一天被送达的订单: SELECT o1.orderNumber, o1.shippedDate, o1.customerNumber FROM orders o1, orders o2 WHERE o1.shippedDate = o2.shippedDate AND o2.orderNumber =...
然后，编辑CTE，生成类似如下的代码段：复制MS SQLWITH InvoiceCTE(InvoiceMonth, Amount)AS(SELECT MONTH(i.InvoiceDate), SUM(il.ExtendedPrice)FROM Sales.InvoiceLines ilINNER JOIN sales.Invoices i ON i.InvoiceID = il.InvoiceIDWHERE i.InvoiceDate BETWEEN '1/1/2013' AND '12/31/2013'GROUP BY MON...
HIERARCHICAL QUERY (CNNTB) 用于实现层次查询。 explain select * from tx connect by prior c1 = c2 start with c3 = 0; #NSET2: [118773, 12500000, 0] #PRJT2: [118773, 12500000, 0]; exp_num(3), is_atom(FALSE) #HIERARCHICAL QUERY: [118773, 12500000, 0]; #PRJT2: [23, 2500, 0]...
In Oracle, you can use specific syntax for hierarchical queries. The WITH clause syntax should still work, but this version is Oracle-specific and may be simpler to understand. Oracle SELECTid,first_name,role,manager_id,levelFROMemployeeSTARTWITHid=1CONNECTBYPRIOR id=manager_idORDERBYlevelASC; ...
Use hierarchyid as a data type to create tables with a hierarchical structure, or to describe the hierarchical structure of data that is stored in another location. Use the hierarchyid functions in Transact-SQL to query and manage hierarchical data. Key properties A value of the hierarchyid data...
Hierarchical Query Examples CONNECT BY Example The following hierarchical query uses theCONNECTBYclause to define the relationship between employees and managers: SELECT employee_id, last_name, manager_id FROM employees CONNECT BY PRIOR employee_id = manager_id; EMPLOYEE_ID LAST_NAME MANAGER_ID ---...
层次数据库(Hierarchical Database, HDB),把数据通过层次结松(树形结构)的方式表现出来。是最古老的数据库之一,现在已经很少使用了。 关系数据库(Relational Database,RDB),关系数据库是现在应用最广泛的数据库。采用由行和列组成的二维表来管理数据。可以使用专门的SQL(Structured Query Language,结构化查询语言)对数...
hierarchical_query_clause::=画像の説明START WITH句では、階層のルート行を指定します。CONNECT BY句では、階層の親/子の行の関連を指定します。NOCYCLEパラメータは、データ内にCONNECT BYループが存在する場合でも問合せで行を戻すようにOracle Databaseに指示します。このパラメータをCONNECT_BY_...