此外,另一种使用FOR LOOP的Implicit Cursor使用方法。 Every time you run either a SQLDML statement or a PL/SQLSELECTINTOstatement, PL/SQL opens animplicit cursor. You can get information about this cursor from its attributes, but you cannot control it. After the statement runs, the database cl...
Implicit Cursor for Loop Note: Here, an implicit cursor FOR LOOP statement prints the name of the supplier and supplier id of the entire item named as DEO whose customer has an ID greater than 100.BEGIN //Beginning of FOR LOOP//
Oracle数据库的Cursor类型包含三种: 静态游标:分为显式(explicit)游标和隐式(implicit)游标;REF游标:是一种引用类型,类似于指针。下面我们一一介绍它们的使用。 1.隐式游标 1)Select …INTO…语句,DML语句,使用隐式Cursor。此外,还有一种使用FOR LOOP的Implicit Cursor用法。 2)可以通过隐式Cusor的属性来了解操作...
在使用显示游标之前,必须先在声明部分定义游标,其定义语法如下:CURSOR cursor_name[(parameter,…)] IS select_statement;说明: 参数parameter形式如下:para_name [IN] data_type [:=|DEFAULT value] (2)打开游标 当打开游标时,ORACLE会执行游标所对应的SELECT语句,并将结果存放到结果集,其定义语法如下:OPEN curso...
隐式游标(Implicit Cursor):在执行一个SQL语句时,服务器将自动创建一个隐式游标,该游标是内存中的工作区,存储了执行SQL语句的结果,可通过游标的属性获得SQL的执行结果及状态信息。多用于只返回一行的SQL语句 4、隐式游标 (ORACLE在创建隐式游标时,默认的游标名为SQL) ...
1. 隐式游标 1 )Select …INTO…语句, DML 语句, 使用隐式 Cursor。 此外, 还有一种使用 FOR LOOP 的Implicit Cursor 用法。 Every time you run either a SQL DML statement or a PL/SQLSELECTINTO statement, PL/SQL opens animplicit cursor. You can get information about this cursor from its ...
Implicit cursorsare session cursors constructed and managed by PL/SQL automatically without being created or defined by a user. PL/SQL opens an implicit cursor each time you run aSELECTor DML statement. Implicit cursors are also called SQL cursors. ...
DBMS_SQL.RETURN_RESULT(l_cursor_1); END IF; OPEN l_cursor_2 FOR SELECT COUNT(*) FROM t1; DBMS_SQL.RETURN_RESULT(l_cursor_2); END; / If we execute this stored procedure from SQL*Plus, it will automatically display the implicit statement results. ...
Performance can be improved substantially by minimizing the number of context switches required to run a particular block or subprogram. When a SQL statement runs inside a loop that uses collection elements as bind variables, the large number of context switches required by the block can cause poor...
“项目设置”对话框的“转换”页面包含一些设置,用来自定义 SSMA 如何将 Oracle 语法转换为 SQL Server 语法。 “项目设置”和“默认项目设置”对话框中提供了“转换”窗格: 要指定用于所有 SSMA 项目的设置,请在“工具”菜单上单击“默认项目设置”,从“迁移目标版本”下拉列表中选择需要为其查看或更改设置...