select sys_connect_by_path(t2.ID, '/') as PATH, t1.id from HTD_DEVICETYPE_RELATION t1 inner join HTD_DEVICETYPE_RESOURCE t2 on t1.CHILD_RESOURCE_TYPE_ID = t2.ID start with t1.parent_resource_type_id = 100 and t1.id > 1 connect by nocycle prior t2.id = t1.parent_resource_ty...
create table hierarchical_functions_tb(VARCHAR2_1 VARCHAR2(100),VARCHAR2_2 VARCHAR2(100)); insert into hierarchical_functions_tb(VARCHAR2_1,VARCHAR2_2) values('hierarchical_functions_tb1','hierarchical_functions_tb2'); select sys_connect_by_path(VARCHAR2_1,'/') from hierarchical_functions_tb...
insert into tab_connect_by (CHILD, PARENT) values(13, 26); insert into tab_connect_by (CHILD, PARENT) values(1, 26); insert into tab_connect_by (CHILD, PARENT) values(12, 26); insert into tab_connect_by (CHILD, PARENT) values(11, 18); insert into tab_connect_by (CHILD, PARENT...
sys_connect_by_path函数就是从start with开始的地方开始遍历,并记下其遍历到的节点,start with开始的地方被视为根节点,将遍历到的路径根据函数中的分隔符,组成一个新的字符串。sys_connect_by_path函数用connect by来寻找下一条记录,直到迭代找不到相应记录为止。概念与递归类似,connect by指定递归(连接)条件,如...
--40,SYS_CONNECT_BY_PATH(COL,C)该函数只能应用于 --树状查询,返回通过c1连接的从根节点的路径,该 --函数必须与connect by子句共同使用 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21.
PostgreSQL从小白到专家,是从入门逐渐能力提升的一个系列教程,内容包括对PG基础的认知、包括安装使用、...
Oracle connect by语法支持异构查询,其中包含了一些特殊的变量:CONNECT_BY_ROOT、CONNECT_BY_ISLEAF、SYS_CONNECT_BY_PATH、CONNECT_BY_ISCYCLE、LEVEL。 https://docs.oracle.com/cd/B19306_01/server.102/b14200/queries003.htm#i2053935 https://docs.oracle.com/cd/B19306_01/server.102/b14200/pseudocolumn...
select COLUMN_NAME,column_id from user_tab_columns where table_name='SYS_USER‘; 表名必须大写,否则查不出来 2.查询出某张表所有字段名,用 ||','|| 分隔 select max(substr(SYS_CONNECT_BY_PATH(COLUMN_NAME,'||'',''||'),2)) col from (select COLUMN_NAME,column_id from user_tab_columns...
sys_connect_by_path(column, char) Is valid only in CONNECT BY queries and returns the path of a column value from root to node. tanh Returns the hyperbolic tangent of argument n. to_blob(char) Converts char strings to BLOB values. Char can be any of the data types (CHAR, VARCHAR2,...
In PostgreSQL, we can achieve a functionality similar toSYS_CONNECT_BY_PATHby concatenating the parent and child record attributes with a char/delimiter in every iteration. See the following code: WITHRECURSIVE cte(emp_no,manager_no,ename,job,level,path)AS(SELECTemp_no,manager_no,ename...