详细信息和文档链接在我之前的回答中：
start with superid = '0' connect by prior id=superid; select level||'层',connect_by_isleaf,lpad(' ',level*5)||id id from test start with superid = '0' connect by prior id=superid; --给出两个以前在"数据库字符串分组相加之四"中的例子来理解start with ... connect by ... --...
What is the path from the top to each position in the tree, by name or by ID: e.g.CEO>Senior Manager>Supervisor South>Minion, or1>2>5>8? What is the path from the top to each employee in the tree, by name or by ID (taking into account employees that may ha...
1 SELECT LEVEL AS 等级, 2 CONNECT_BY_ISLEAF AS 是否是叶子节点, 3 LPAD(' ', LEVEL * 2 - 1) || SYS_CONNECT_BY_PATH(ENAME, '=>'), 4 E.* 5 FROM EMP E 6 CONNECT BY PRIOR E.EMPNO = E.MGR 7 START WITH E.MGR IS NULL 8 ORDER SIBLINGS BY E.ENAME; 1. connect_by_iscycle(...
PRIOR被置于CONNECT BY子句中等号的前面时,则强制从根节点到叶节点的顺序检索,即由父节点向子节点方向通过树结构,我们称之为自顶向下的方式。如: CONNECT BY PRIOR EMPNO=MGR PIROR运算符被置于CONNECT BY 子句中等号的后面时,则强制从叶节点到根节点的顺序检索,即由子节点向父节点方向通过树结构,我们称之为自...
CONNECT BY LOOP A loop in user data generates an �ORA-01436: CONNECT BY loop in user data� error. A loop is defined in the Oracle Database SQL Language Reference (11.1) documentation as: A loop occurs if one row is both the parent (or grandparent or direct ancestor) and a child...
在某些复杂查询的场景下，需要使用递归功能。通过CONNECT BY实现递归SQL是Oracle特有的方言之一，目前openGauss无法兼容CONNECT BY关键字，需要通过使用递归CTE查询替代。postgres=# SELECT *, LEVEL FROM te1 CONNECT BY PRIOR id = pid; ERROR: syntax error at or near "BY"LINE 3: CONNECT BY PRIO...
The Oracle SQL syntax requires you to specify parameters in your query by prefixing them with a colon (:) instead of at sign (@). Be sure to set these correctly in the SQL statements in your metadata. If your Oracle connection requires explicit user ID and password parameters in the conn...
新的 tcsh 版本拒絕使用破折號或等號的 setenv 變 數名稱 在 Oracle Solaris 10 作業系統中,tcsh 已升級至版本 6.12.此版本不再接受名稱包含破 折號或等號的環境變數.包含 setenv 行且在較早 Oracle Solaris 版本中運作的程序 檔,可能會在目前的發行版本中產生錯誤.螢幕上將顯示下列錯誤訊息: setenv: Syntax ...
EXECSyntax = T Failover = T FailoverDelay = 10 FailoverRetryCount = 10 FetchBufferSize = 64000 ForceWCHAR = F LobPrefetchSize = 8192 Lobs = T Longs = T MaxLargeData = 0 MaxTokenSize = 8192 MetadataIdDefault = F QueryTimeout = T ...