- 1、本文档共37页,可阅读全部内容。
- 2、有哪些信誉好的足球投注网站(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
- 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载。
- 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
查看更多
oracle知识点总结(Oracle knowledge point summary)
oracle知识点总结(Oracle knowledge point summary)
What is pl/SQL
Pl/SQL (procedural language/SQL) is an extension of the Oracle on the standard SQL language, pl/SQL allows embedded SQL language, not only can define variables and constants, allows the use of conditional statement and circular statement, allows the use of exception handling all kinds of errors, which makes it become more powerful.
Ii. The need for pl/SQL learning
1. Improve the performance of the application.
2. Modular design ideas.
3. Reduce network transmission.
4. Improve security.
Iii. Preparation of specifications
1, comments,
Single line comment --
SQL select * from emp where empno = 7788; -- obtain employee information
Multiline comment
/ *... * /
2. Nomenclature for identifying symbols
(1) when defining variables, use v_ as the prefix v_sal.
(2) when defining constants, it is recommended to prefix c_rate with c_.
(3) when defining the cursor, it is recommended to use _cursor as the suffix emp_cursor.
(4) when an exception is defined, an e_ is recommended as a prefix e_error.
Four, block
Block (block) is the basic program unit of pl/SQL, and writing pl/SQL programs is essentially writing pl/SQL blocks. To complete a relatively simple application, you might simply write a pl/SQL fast. But if you want to implement complex functions, you may need to nest other pl/SQL fast in a pl/SQL block.
1. Block structure diagram
The pl/SQL block consists of three parts: the definition part, the execution part, and the exception handling section.
Declear: the definition begins with the declare, which is optional. Define constants, variables, cursor exceptions, complex data types.
Begin: the execution part begins with begin, which is necessary.
Exception: exception handling is started with exception, which is optional.
A, contains the definition part and the execution part of the pl/SQL block
declare
V_ename varchar2 (5); -- defines string variables
The begin
Select ename int o v_ename from emp where empno = no;
D
您可能关注的文档
- 2010驾照理论考试模拟题(Test simulation of driver's license in 2010).doc
- 2010经济员铁路运输(2010 economic worker rail transport).doc
- 2011-2012学年度第一学期七年级期中考试试卷(The first semester of the 2011-2012 academic year).doc
- 2011《管理与法规》91道真题+答案(Management and regulation 91).doc
- 2011二级法规试卷真题(The 2011 secondary regulations paper).doc
- 2011二级建造师法规与知识(Second class ii builder regulations and knowledge).doc
- 2011安徽高考文综考点(2011 anhui college entrance examination and writing test center).doc
- 2011安徽高考语文(2011 anhui college entrance examination language).doc
- 2011年上海高考历史试题及答案(2011 Shanghai college entrance examination history questions and answers).doc
- 2011年UGNX-CAD认证考试理论概念题(The concept of ugnx-cad certification test in 2011).doc
文档评论(0)