The query associated with a cursor variable can reference any variable in its scope. Changing the values of the variables later does not change the result set. The following code opens a cursor variable for a query that references the variable factor. ...
SQL> create table mytest(name varchar2(30),passwd varchar2(30)); 2、创建过程 SQL> create procedure sp_prol is begin --执行部分 insert into mytest('hjadsfhas','sdkhfdsj'); end; / 也可以使用(replace 表示如果有sp_prol就替换) SQL> create or replace procedure sp_prol is 2 begin 3...
Kraft Heinz:500Code language: SQL (Structured Query Language) (sql) This example illustrates how to declare variables that anchor to another variable: DECLARE l_credit_limit customers.credit_limit%TYPE; l_average_credit l_credit_limit%TYPE; l_max_credit l_credit_limit%TYPE; l_min_credit l_...
variable相当于一个sql*plus环境的全局变量,declare里定义的是pl/sql中的局部变量。
variable_name = value; Alternatively, you can use the := assignment operator: variable_name := value; Basic PL/pgSQL variable example 1) Declare variables The following example shows how to declare and initialize variables: do $$ declare counter integer = 1; first_name varchar(50) = 'John...
variable是sqlplus中定义变量的命令。他定义的变量在一个sqlplus连接中有效。SQL> show user USER 为"YANGTK"SQL> var SP2-0568: 未说明结合变量。SQL> var test number SQL> var 变量 test 数据类型 NUMBER SQL> conn / as sysdba 已连接。SQL> show user USER 为"SYS"SQL> var 变量 ...
PL/SQL是由Oracle开发,专用于Oracle的一种程序设计语言; PL代表Procedural Language; SQL代表Structured Query Language; PL/SQL是Oracle数据库对SQL语句的扩展,增加了编程语言的特点; PL/SQL 包含过程化语句和SQL语句数据操作和查询语句被包含在PL/SQL代码的程序单元中(PL/SQL块),经过逻辑判断、循环等操作完成复杂的...
23,使用Query Analyzer,查看SQL语句的查询计划和评估分析是否是优化的SQL.一般的20%的代码占据了80%的资源,我们优化的重点是这些慢的地方. 24,如果使用了IN或者OR等时发现查询没有走索引,使用显示申明指定索引: Select * FROM PersonMember (INDEX = IX_Title) Where processid IN ('男','女') ...
The cursor name is an undeclared identifier, not the name of a PL/SQL variable. You cannot assign values to a cursor name or use it in an expression. However, cursors and variables follow the same scoping rules. Naming cursors after database tables is allowed but not recommended. ...