Plsql 简明教程
PL/SQL Tutorial
PL/SQL Tutorial
PL/SQL，意为程序化语言的 Structured Query Language （SQL）扩展。它结合了 SQL 以及编程语言的过程化特性。它是由 Oracle Corporation 在 90 年代早期开发的，目的是增强 SQL 的功能。PL/SQL 是嵌入 Oracle 数据库的三个主要编程语言之一，另外两个是 SQL 本身和 Java 。
PL/SQL, which stands for Procedural Language extensions to the Structured Query Language (SQL). It is a combination of SQL along with the procedural features of programming languages. It was developed by Oracle Corporation in the early 90’s to enhance the capabilities of SQL. PL/SQL is one of three key programming languages embedded in the Oracle Database, along with SQL itself and Java.
在本教程中，我们将帮助你深入理解 PL/SQL，以继续学习 Oracle 数据库和其他高级 RDBMS concepts 。
In this tutorial, we’ll give you a great understanding of PL/SQL to proceed with the Oracle database and other advanced RDBMS concepts.
Purpose of PL/SQL
PL/SQL 的目的是将数据库命令与过程化编程语言合并在一起。它为构建在 Oracle 数据库上运行的关键应用程序提供了更全面的编程解决方案。
The purpose of PL/SQL is to merge database commands with procedural programming language. It offers more complete programming solutions for building critical applications that operate on the Oracle database.
Features of PL/SQL
PL/SQL 具有以下特性 -
PL/SQL has the following features −
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PL/SQL is tightly integrated with SQL.
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It offers extensive extensive error checking mechanisms.
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It supports numerous data types for flexible data handling.
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Includes a variety of programming structures, such as loops and conditionals. Includes a variety of programming structures, such as loops and conditionals.
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It supports structured programming through functions and procedures.
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It supports object-oriented programming, enabling more complex data handling and manipulation.
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It supports the web application development and server pages.
Why to learn PL/SQL?
学习 PL/SQL 对于对数据库和其他高级 RDBMS 技术感兴趣的人来说是一项必备技能。PL/SQL 具有各种优势，使其成为数据库开发人员的必备技能 −
Learning PL/SQL is an essential skill for persons who are interested in databases and other advanced RDBMS technologies. PL/SQL offers various benefits, making it an essential skill for database developers −
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Ease of Use: PL/SQL is straightforward to write and read, featuring block-structured syntax which simplifies programming and debugging.
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Portability: Programs written in PL/SQL are fully portable across different Oracle databases, ensuring consistency and ease of migration.
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Tight SQL Integration: PL/SQL is tightly integrated with SQL, allowing for efficient querying, transforming, and updating of data within a database.
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High Performance: It reduces network traffic by sending entire blocks of statements to the database at once, thus improving performance.
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Security: It includes robust security features to protect database integrity.
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Object-Oriented Support: It supports object-oriented programming, and allows you to define object types that can be used in object-oriented designs.
PL/SQL Block Structured
PL/SQL 遵循以块为结构的方法，将程序分成逻辑代码块。每个块包含三个主要部分 −
PL/SQL follows a block-structured approach, dividing programs into logical blocks of code. Each block consists of three main sections −
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Declarations: This section, starting with the keyword DECLARE, is optional and used for defining variables, cursors, subprograms, and other elements required within the block.
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Executable Commands: Enclosed between the keywords BEGIN and END, this mandatory section contains executable PL/SQL statements. It must include at least one executable line of code, even if it’s just a NULL command indicating no action.
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Exception Handling: This starts with the keyword EXCEPTION, this optional section deals with handling errors in the program through defined exceptions.
PL/SQL 语句以一个分号（;）结尾。此外，可以使用 BEGIN 和 END 关键字相互嵌套块。
PL/SQL statements are terminated with a semicolon(;). Additionally, blocks can be nested within each other using BEGIN and END keywords.
Applications of PL/SQL
PL/SQL 广泛用于各种应用，包括 -
PL/SQL is widely used in various applications, including −
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Database Security: It implements robust security measures within the database.
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XML Management: Generating and managing XML documents within the database.
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Linking Databases to Web Pages: Integrates databases with web applications.
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Automation: Automating database administration tasks for efficient management.
Who Should Learn PL/SQL?
此教程旨在为打算学习 PL/SQL 编程语言的软件专业人员提供简单便捷的步骤。本教程将帮助您深入了解 PL/SQL 编程概念，在完成本教程后，您的专业知识将达到中级水平，您可以从此基础提升到更高的专业水平。
This tutorial is designed for Software Professionals, who are willing to learn PL/SQL Programming Language in simple and easy steps. This tutorial will give you a great understanding of PL/SQL Programming concepts, and after completing this tutorial, you will be at an intermediate level of expertise from where you can take yourself to a higher level of expertise.
Prerequisites to learn PL/SQL
在继续本教程之前，您应基本了解软件概念，如什么是数据库、源代码、文本编辑器和程序执行等。如果您已经了解 SQL 和其他计算机编程语言，那么继续学习会更有益。开始吧！
Before proceeding with this tutorial, you should have a basic understanding of software concepts like what is database, source code, text editor, and execution of programs, etc. If you already have an understanding of SQL and other computer programming languages, then it will be an added advantage to proceed. Let’s get started!
PL/SQL Jobs and Opportunities
精通 PL/SQL 创造了多种职业机会，如 -
Proficiency in PL/SQL opens up various career opportunities, such as −
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Oracle PL/SQL Programmer
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PL/SQL Developer
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Database Developer
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Data Analyst
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Database Testers
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Data Scientist
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ETL Developer
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Database Migration Expert
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Cloud Database Expert etc
掌握 PL/SQL 后，您可以在数据库管理和开发以及创建安全可扩展的应用方面提升自己的职业机会。
By mastering PL/SQL, you can increase your career opportunities in database management and development, as well as in creating secure and scalable applications.