Oracle Database need not verify thata cursor is in the cache because it cannot be deallocated while an applicationcursor associated with it is open.
Oracle Database need not verify thata cursor is in the cache because it cannot be deallocated while an applicationcursor associated with it is open.
Cursor不能共享主要是指子游标中存储的执行计划不能共享,此处只涉及shared cursor中parent cursor/ child cursor结构信息: shared cursor 指library cache中的一种库缓存对象,是缓存在library cache中的SQL语句/匿名PL/SQL语句所对应的库缓存对象,具体存储SQL文本、解析树、SQL涉及的对象定义、所使用的绑定变量类型和长...
The best practice is to write sharable SQL and use the default of EXACT for CURSOR_SHARING. However, for applications with many similar statements, setting CURSOR_SHARING can significantly improve cursor sharing, resulting in reduced memory usage, faster parses, and reduced latch contention. Consider...
首先，我有一个返回ref_cursor的过程Oracle存储过程: CREATE OR REPLACE PROCEDURE getcity ( city...
A partial update may be performed only with Cursor.putCurrent. A null or partial DatabaseEntry output parameter may also be used in other cases, for example, to retrieve a partial key item. However, in practice this has limited value since the entire key is usually needed by the ...
Some Source objects cannot have a Cursor. You cannot retrieve results with a Cursor for a Source if one of the following is true: The Source has an input. The Source has no elements or the Source has an input that has no elements. The query is not computationally possible; for example,...
Example 1: Cursor For Loop With Simple Explicit Cursor SET SERVEROUTPUT ON; DECLARE CURSOR cur_RebellionRider IS SELECT first_name, last_name FROM employees WHERE employee_id >200; BEGIN FOR L_IDX IN cur_RebellionRider LOOP DBMS_OUTPUT.PUT_LINE(L_IDX.first_name||' '||L_IDX.last_name)...
一、Oracle数据库实例、用户、目录及session会话查看: 1、ORACLE SID查看设置 查看SID、用户名 $ env|grep SID 、select * from v$instance、select instance_name,host_name from v$instance; 查看数据库所有用户及用户状态: SQL> select usernames,account_status from dba_users; ...
双下划线前缀在 Python 中具有特殊含义,因为该语言实际上不允许您声明私有变量(类中一切皆为公有),从而增加了变量的访问难度:变量是通过 _Class__Member 语法(上例中的 _HR__db 和 _HR_cursor)公开的。同时,我们在该类中声明 __enter__ 和 __exit__ 方法,这样我们可以使用WITH 语句,在 WITH 代码块结束...