In this chapter, we will discuss the Basic Syntax of PL/SQL which is a block-structured language; this means that the PL/SQL programs are divided and written in logical blocks of code. Each block consists of three sub-parts −S.NoSections & Description 1 Declarations This section starts ...
所有的SQL数据操作语句都可以用于执行部分,PL/SQL块不能在屏幕上显示SELECT语句的输出。SELECT语句必须包括一个INTO子串或者是游标的一部分,执行部分使用的变量和常量必须首先在声明部分声明,执行部分必须至少包括一条可执行语句,NULL是一条合法的可执行语句,事物控制语句COMMIT和ROLLBACK可以在执行部分使用,数据定义语言DDL...
·函数:Create or replace function funcname(参数列表) return返回值as PL/SQL语句块 5.游标的定义为:用游标来指代一个DML SQL操作返回的结果集。即当一个对数据库的查询操作返回一组结果集时,用游标来标注这组结果集,以后通过对游标的操作来获取结果集中的数据信息。这里特别提出游标的概念,是因为它在PL/SQL...
PL/SQL Basic --PL/SQL块结构DECLARE/**定义部分-定义常量,变量,复杂数据类型,游标。 可选 没有;*/BEGIN/**执行部分-sql语句 必须 没有;*/EXCEPTION/**例外处理部分-处理运行错误 可选 没有;*/END;/*块结束标志 必须;*/setserveroutputonBEGINDBMS_OUTPUT.PUT_LINE('Hello');END;DECLAREv_enameVARCHAR(...
You should have the SQL prompt where you will write your PL/SQL commands and scripts −Text EditorRunning large programs from the command prompt may land you in inadvertently losing some of the work. It is always recommended to use the command files. To use the command files −...
This chapter covers basic reference material on how to write programs in PL/SQL and their examples. PL/SQL allows dependencies between commands within the same block of code. It also allows for parameter passing up and down code block hierarchies. PL/SQL contains a definition of variable scope...
一.PL/SQL 定义 PL/SQL is theOracle Database procedural extension to SQL. PL/SQL is integrated with thedatabase, supporting all Oracle SQL statements, functions, and datatypes. Applications written in database APIs can invoke PL/SQL storedsubprograms and send PL/SQL code blocks ...
PL/SQL Block Structure A block is the most basic unit in PL/SQL. All PL/SQL programs are combined into blocks. These blocks can also be nested within one another. Usually, PL/SQL blocks combine statements that represent a single logical task. Therefore, different tasks within a single progr...
The programming statements that can be used in a PL/SQL application include: assignment, DELETE, EXECUTE IMMEDIATE, INSERT, NULL, SELECT INTO, and UPDATE.
PL/SQL Basic LoopBasic loop or simple loop is preferred in PL/SQL code when there is no surety about how many times the block of code is to be repeated. When we use the basic loop the code block will be executed at least once....