Monthly Archives: October 2007

note about studying ALV in abap webdynpro

Simple Example for Using ALV1. create component2. create component controller’s context NODE_FLIGHT, dictionary structure: SFLIGHT, attribute of structure: CARRID, CONNID NODE_FLIGHTTAB, dictionary structure: SFLIGHT, cardinality: 0..n, attribute of structure: CARRID, CONNID, FLDATE, CURRENCY, PLANETYPE, SEATSMAX, SEATSOCC and PAYMENTSUM clear property of dictionary structure to prevent ALV component from showing all the fields of structure SFLIGHT3. [...]

ABAP OO 的一些基本概念和语法

1. 类的基本知识 声明和实现类: CLASS c1 DEFINITION. ENDCLASS. CLASS c1 IMPLEMENTATION ENDCLASS. 可见性设置 PUBLIC SECTION. PROTECTED SECTION. PRIVATE SECTION. 实例变量和方法 DATA name TYPE string. METHODS m1 IMPORTING msg TYPE string. 静态变量和方法 CLASS-DATA pi TYPE i. CLASS-METHODS m3. 方法实现 METHOD m1. ENDMETHOD. 构造函数 instance level: METHODS constructor. class level: CLASS-METHODS class_constructor. 2. 类的实例化和访问 创建实例 DATA v1 TYPE [...]

Note about studying ABAP WebDnypro

Source Tutorial URL:Web Dynpro for ABAP Prepare: Question: Can not open view design preview Solution: Active necessary service use transaction SCIF, NOTES: 1008689 Tutorial 1- Create a simple Web Dynpro Application 1. create Component 2. create View 3. embed View in the Main window 4. create View Context Node, name is FLIGHT_NODE, structure is SFLIGHT [...]

[转载]Web Dynpro: ABAP or Java?

原文地址: Web Dynpro: ABAP or Java? Ah. The beauty and agony of choice. As you may have heard, SAP NetWeaver 2004s will support Web Dynpro (WD) development using ABAP – previously only a Java domain. As a SAP customer and developer you now have a choice to make: Do I use ABAP or Java to [...]


尽管我们在SQL的FROM子句可以写多个表连接的语句,但是实际上Oracle每次只能连接两个表,多个表连接被拆分成多次的两个表连接,具体如何拆分要视Oracle的执行计划而定。 常用的有三种连接方式: 一、Sort Merge Join 把两个表各自符合条件的记录取出来并进行排序,然后对两个集合按照Join的条件进行连接 二、Nested Loops 这种情况下连接的表分为外部表和内部表,外部表是处于嵌套循环外层的表,一般情况下这个表符合条件的记录应该尽可能的少。 大概的过程是对外部表符合条件的记录进行循环,在每个循环中,在内部表中查找符合Join条件的记录。 这种Join方法的好处是能够尽快返回部分结果集。 三、Hash Join 将符合条件记录较少表的记录放到内存中,按照Join条件的字段计算Hash值,然后在另外一张表中查找符合条件的记录,按照Join条件字段的Hash值与从第一个表提取到内存中的记录进行匹配。 Hash Join只适用于等值连接的情况。 更详细的介绍请参考下面的BLOG: ORACLE执行计划的一些基本概念 ,写的非常不错!

Be careful of chain statement in Update SQL!

The ‘colon and comma’ logic in the program fragment UPDATE SCUSTOM SET: DISCOUNT = ’003′, TELEPHONE = ’0621/444444′ WHERE ID = ’00017777′. defines statement chains, NOT through a single statement which updates the discount and thetelephone number of the customer with the customer number ’00017777′, BUT by means of two statements where the first updates [...]