Getting Started with ABAP

New to ABAP? Refer:

http://scn.sap.com/docs/DOC-7940


Source: http://scn.sap.com

Learn OO-ABAP

Part 1:
http://scn.sap.com/docs/DOC-10236

Part 2:
http://scn.sap.com/docs/DOC-10237

Part 3:
http://scn.sap.com/docs/DOC-10238

Part 4:
http://scn.sap.com/docs/DOC-10239

Part 5:
http://scn.sap.com/docs/DOC-10240


* Courtesy SAP SCN.

SAP Career Blog Links

For all questions and doubts on career in SAP refer the link:
http://scn.sap.com/community/career-center/blog/2012/06/19/sap-career-blog-links

* Copy from scn.sap.com

Client copy

A client copy does not "generate a new system". It is used to transferinformation between clients within the same system or to another system atthe same release and db level.

Procedure to create:
If it is a fresh installation, do this --

1. SCC4 --> Create client no. and fill other details.

2. Logon to the newly created client with SAP* and PASS as password.

3. SCCL --> choose any profile (preferably SAP_ALL), source client 000 and target client .

4. Preferably do a test run initially to check if it can go well.

5. As a care check space in databases.

You can do Client copies remotely or do an export/import of data. Please study the dependancies of client dependant/independant data rel.notes.
Export: If you need to do a full client copy and database is more than 50 or 60gb, the import may tae little long time. Export of the full data can be done with SAP_ALLprofile in Source system. SCC4 >> Export the data with required profiles. It will create data and cofiles under os level. (usr/sap/trans/data, cofiles).The export may take of 8 to 20 hrs dependts on data.The import may take several days based on the size of the data. You need to set some parameters before you start the import. After the succefull import you need to do post processing for client copy with request in SCC8.

It depends upon what method you want to do client copy.
If you say remote client copy, i will suggest you against it because it takes hell lot of time to do client copy and any break for a moment in network connection will cause failure in client copy.If you are exporting the client then as such there is no problem, just remember the sequence in which you import the three (or two) transport requests.AND, keep enough free space in Tablespaces of Target server.

Procedure :
1.Check Sufficeint space at OS level to keep extracted data from source client

2.Export the client using following path or scc8Tools (r) Administration (r) Administration (r) Client Admin. (r) Client Transport (r) Client Export. Select the data to be copied using a profile. (if u wnat client specific and cross client data use profile sap_expc). before importing ensure that all table spaces have enough sapce for this check source system table spaces and allocate table space accordingly)

3.Now create new client in target system

4.now import those requests in target client using stms or scc6

5.Now perform post processingTools (r) Administration (r) Administration (r) Client administration (r) Client transport(r) Import editing

There are 3 standard clients in sap r/3 system. They are 000, 001 and 066. These three clients come with default users along with default passwords. I have listed in the following paragraphs.

What is a client: A client is an independent unit within the R/3 system or an area in the system with data on which a user works.

We have to do client copy right after installation of the software as our first job to begin the technical phase of implementation. We have to copy from one of the standard clients available. We can use copied clients for testing, training or for starting real customization.

We will discuss about what is data and what types of data is available in the sap R/3 system before going into the explaining of definition of the standard clients.

Data: The information residing in the database tables is called data. There are different types of data involved in the R/3 system. They are client dependent data, client-independent data and the client repository data.

Client dependent data: The data which is accessible through a particular client is called client dependent data. The user data is one of the examples of client dependent data.

Client-independent data: The data which can be accessible from any client or which is common to any client in the system is called client-independent data. The transaction code or t-code data is example of the client-independent data.

Client repository data: The different application programs which makes SAP runs is called client repository data. The transaction data, application data, customizing data are other different types of data of the sap r/3 system.

Standard clients of the SAP R/3 system:

000 Client: This client is called as master client in the r/3 system. This client is included in the sap r/3 system as default. We can find this client in the system as soon as we install sap r/3 software. Client 000 contains a simple organizational structure of a test company and includes parameters for all applications, standard settings, configurations for the control of standard transactions and examples to be used in many different profiles of the business applications. For these reasons, 000 is a special client for the R/3 system since it contains the client−independent settings. We can access the entire standard data with this client. We should not do any changes in the data through master client. The default users of this client are mentioned below along with default passwords.

• User name: sap*
• Password: This password will be set by the person during the sap r/3 installation
• User name: ddic
• Password: This password will be set by the person during the sap r/3 installation

001 client: This client is best example for customizing or development client and we can access entire customizing data. This client is a copy of the 000 client including the test company. This client’s settings are client-independent if it is configured or customized. This client is reserved for the activities of preparing a r/3 system for the production environment. The customers of the SAP normally use this client as a source for copying other new clients. The default users and passwords of this client are listed below.

• User name: sap*
• Password: 06071992
• User name: ddic
• Password: 19920706

066 Client: This client also called as early watch client which is reserved for sap access. SAP will access their customer systems using this client to perform the Early Watch service. SAP will generate the performance report of its customer system and this report is called as Early Watch report. The default users of this client are listed below.

• User name: sap*
• Password: 06071992
• User name: earlywatch
• Password: support

Roles of Basis Consultant

SAP basis consultant should have primarily the knowledge of network administration. Then only he can install and configure operating system perfectly to install a SAP system. Because any SAP system mostly depends on the underlying database, he also should be able to install, configure and administer any type of relational database system. He should have through understanding about different computer programs or applications to use the sap system properly. He should be able to understand the complete structure and functionality of the entire SAP R/3 system. The following are the general day to day roles of a SAP basis consultant.

• Basis consultant should be able to handle the administration of sap including the installation, configuration and maintenance.
• Installation may include SAP R/3, ECC, Net weaver, Net Weaver components, Solution Manager etc..
• He should be able to do user administration like creating and deleting users, assigning and resetting passwords, locking and unlocking users.
• He should be able to do client administration like local client copy,  remote client copy, create and deleting clients.
• He should be able to create and restore data backups
• He should be able to do printer or spool configuration and administration
• He should be able to create RFCs and should be able to configure TMS (Transport Management System)
• He should be able to monitor and manage the servers, background jobs, performacne of the system
• He should be able to create roles using different methods like transactions, direct objects, missing authorizations, restrictions…etc
• He should be able to analyze and fix missing authorizations
• He should be able to do the sap license management
• He should be able to troubleshoot security or authorization problems using SU53, ST01 and SUIM
• He should be able to monitor the status of work processes, application servers and system logs etc…
• He should be able to analyze the ABAP dumps
• He should be able to manage the database space allocation
• He should be able to do system copies
• He should be able to rectify any type of problem related to opearing systems
• He should be able to configure SAP GUI at client computers
• He should be able to rectify minor networking problems
• He should have through understanding of IP address configurations and pinging concept
• He must able to troubleshoot any client or server problems.

SAP Sizing

Before SAP software is installed SAP environment must be planned.

The process of planning the environment is called "sizing".

Following decisions must be made:

§  How many installations would be there in the landscape (see next article).

§  How many application servers (middle tier) will be deployed to share the load.

§  What SAP components will be deployed.

§  How the components will be they deployed.

§  What would be the size of the database and hence the disk capacity of the database server.

§  How scalable the system needs to be (How fast the company will grow).

§  What would be the disaster recovery plan.

§  What should be the availability of the system. (Time when system is not down).

§  What kind of performance is acceptable especially when workload is high (month-end processes).

The above questions are answered by IT department working closely with SAP's implementation consultants (integrator) and the hardware partners.

The design process should start early.

Business should be engaged as quickly as possible to gather requirements.

Then SAP integrator and hardware partners should translate these requirements into sizing recommendations.

SAP Instances

An SAP environment consists of multiple SAP instances or installations.

Most common approach is to have three installations (also refer to as three-system landscape):

§  Development System - Used by developers to develop or modify the software.

§  Quality assurance or Test System - Used by testers to test the new development.

§  Production System - Used by users to run the business.

When developers modify the applications or functional consultant modifies any setup, changes are first promoted to the Test System where testers test the changes. Once approved changes are moved over to the Production System.

Some companies keep a separate installation as "sandbox".

Sandbox could be used for technical training. New things could be tried safely in this environment.

Some companies also keep dedicates systems for testing new releases. Such systems are called "Stage" systems. Other companies would simply test the new releases on their Test Systems.

From a technical roadmap perspective it is important to decide how many SAP installations would be there in your landscape. This has to be figured out before starting the actual installation. This decision is part of the "sizing". Each installation would have its own application tier and a database tier. Hence each installation would be using at least two machines.

Technology Stack: ABAP and Java

SAP components are either built on ABAP technology stack or on Java technology stack.

ABAP stands for Advanced Business Application Programming. It is a high level programming language created by SAP. Before sizing the SAP installation it is import to determine which technical stack would be deployed. The SAP NetWeaver platform supports both technology stacks: ABAP and Java. Either one is support as well as both are supported in conjunction. SAP components that are being implemented dictates which technology stack company will end up using.

For example Employee Self-Service component requires Java whereas ERP 6.0 component requires ABAP.

The SAP Master Guides help you find out which underlying technology stack (ABAP or Java) is behind which module.

SAP Releases

SAP R/2

Initial SAP release was known as SAP R/2. This release was designed to work on mainframe computers. Mainframe computing is two tier architecture. The database and application sits on the mainframe computer and users access the application through terminals. Terminal is simply a dumb box without a CPU; keyboard and a monitor is attached to this box. In comparison to three-tiered architecture you can think mainframe as applications server and a database server combined and a terminal as a presentation layer

SAP R/3

The next generation of SAP software was called SAP R/3.This was the most popular release. Even today the term SAP is used synonymously with SAP R/3 (the usage may not true anymore). SAP R/3 was based on client server architecture. The presentation layer and the business logic would reside on a desktop. The database would run on a database server. All desktops would connect to the database server to write and read data. If one has to upgrade the business logic then the entire desktop would need to be patched.

SAP ECC

Finally SAP ECC arrived. ECC stands for ERP Central Component. SAP ECC is based on three tiered architecture (Presentation Layer, Business Logic Layer, Database Layer).This architecture is very flexible and scalable and would also support SOA as well. The main strength of SAP ECC in the NetWeaver software running underneath it as a common technology. SAP ECC is the latest generation of SAP business software.

Primary objective of a company is to make money. A business produces either a product or a service in order to make money. Products or services are sold to customers. The raw material and operating supplies are purchased from vendors. The company needs to manage customers and vendors. Also the company would produce reports each month (or each period) showing the progress of the business. Also the company would need to manage all aspects of the business e.g. employees, bank accounts, inventory etc.In order to make things manageable there would be various departments in the company each looking after a particular aspect of the business e.g. Finance Department, Manufacturing Department, Human Resources Department etc. Each department would need to use some kind of software in order to manage their day to day activities. Enterprise Resource Planning (ERP) software is an enterprise wide solution. ERP software consists of modules. Each department of the company could use one or more modules (specific to that department) of the ERP software in order to manage its day to day tasks. All modules of ERP software are connected. This way management can have a view on the company as a whole. SAP is leading ERP software with largest market share.

Usually the term SAP refers to both the company and its software.SAP AG is a company based in Walldorf, Germany. AG in German stands for "Incorporated". SAP is pronounced as s-a-p, not as sap.

SAP was founded in 1972 in city of Mannheim, Germany. SAP AG is an older company than both Oracle and Microsoft. A group of five ex-IBM engineers formed this company. The idea was to develop a software that integrates business functions in a manner that reflects industry best practices. This way a company could replace multiple software (financial, warehousing, production planning) with one single software having integrated modules. Maintaining a single version of truth results in: synergies and communication benefits. This idea soon evolved into a product called "System, Applications, and Products in Data Processing" (SAP). 
In German SAP stands for "Systemanalyse und Programmentwicklung".

SAP was designed in such a way that it could be installed on a variety of hardware platforms and could work with variety of back-end databases

This gave its customers flexibility and is a major factor in propelling SAP into forefront.

SAP supports:

§  More than 40 languages

§  More than 50 currencies

§  More than 30 industry specific solutions

§  More than 20 combinations of hardware platforms/database/operating systems

Within two decades of its birth, SAP was not the only business software vendor. IBM was facing a tough competition from SAP

Various players emerged including:

§  BAAN

§  Oracle Corporation

§  PeopleSoft

§  JD Edwards

Some small players start gaining grounds as well including:

§  Great Plains

§  Navision SAP remained the leader throughout, mainly due its support for diverse platform.

JD Edwards was purchased by PeopleSoft, which was later on purchased by Oracle Corporation. Currently, Oracle Corporation is number one rival for SAP with its software called Oracle E-Business Suite.

SAP AG is based in Germany and listed on New York Stock Exchange (NYSE) under the symbol of SAP. The company has about 43,000 employees. SAP has about 2000 support partners. About 46,000 customers have purchased SAP software and more than 100,000+ installations are in place around the globe. The company does business in more than 50 countries. There are more than one million SAP end-users. Primary competitors of SAP are Oracle and Microsoft.

All three, SAP, Oracle, and Microsoft provide:

§  Business software for large enterprise

§  Solutions for small and medium sized business

§  Software development platforms

§  Ability to tie together disparate systems (Integration Solution)

All three help sustain one another. Examples are:

§  Most installation of SAP runs on Oracle database (Oracle Corporation makes database as well as their own business software).

§  Microsoft Windows is most popular desktop operating system to access SAP software

SAP instance

SAP instance resides on an Application Server under the directory: 

Windows: x:\usr\sap\sapsid 
Unix/Linux: /usr/sap/sapsid 

The SAP instance on an Application Server communicates with a database associated with this instance. 

SAP instance on an Application Server together with its associated database is called an "SAP System". 

The term "SAP System" is also known as "SAP Installation". 

When you talk about an SAP System or an SAP Installation, you are talking about an SAPSID folder on an Application Server and the database associated with this folder.

Multiple SAP Instances

One Application Server (or host) could contain multiple SAP instances. 

In other words there would be multiple SAPSID folders under the directory /usr/sap (x:\user\sap on Window). 

Where SAPSID is the actual name of the SAP identifier; for example: PROD, TEST etc. 

Each SAPSID folder would point to its own database. 

SAP System refers to the pair of SAP instance and its database. 

The folder /usr/sap could contain more than one SAP instance. 

It is important to know the difference between SAP System (pairing) and SAP instance (folder).

Load Balancing

When number of users increases, load balancing is implemented. 

The SAPSID folder is simply cloned to more than one Application Servers. 

Load is shared by making users connect to different Application Servers. 

Load balancing software controls which user would connect to would Application Server. 

SAPSID folders on all Application Servers would be talking to the same database. 

All sibling SAPSID folders together with their database would be called one SAP System. 

When load balancing is implemented, SAP System would consist of multiple SAPSID folders on difference Application Server machines and a database. 

An Application Server may host more than one SAP instance under the directory /usr/sap

Operating System for SAP

Following factors should be considered when deciding which Operating System to use with SAP.

§  Current skill set of IT staff, cost of retraining, and cost of hiring new staff

§  Support from operating system vendors

§  Confidence on the Operating System and the vendor

§  Verifiable client references

§  Relationship of operating system vendor with SAP

64-bit OS

Starting 2007, SAP software is only supported on 64-bit operating systems. 64-bit hardware is more prevalent. The demand for 32-bit hardware and therefore 32-bit operating system is reducing with time. For SAP systems, only 64-bit hardware should be considered unless you have good reasons to support older versions of SAP or some other related software that only runs on 32-bit environment.

Selecting OS

When making a decision on which Operating System to use with your SAP system, you should keep in mind following features:

§  Memory Management

§  Crash Recovery

§  Patch Management

§  Security

§  Clustering Capabilities

§  Support for third party management utilities

§  Presence of built-in management utilities

It may or may not be compatible with your IT department's vision to invest in new toolsets. In that case you also have to make sure that your existing monitoring applications, virus scanning software and backup solutions would work with this operating system.

SAP OS Directory Structure

On UNIX and Linux OS, SAP is installed on the directory: 

/usr/sap 
On Windows SAP resides in: 
x:\usr\sap 
Where x is a drive letter.

On windows the folder x:\usr\sap is shared as SAPMNT. 

You can access this folder from other machine as \\machinename\sapmnt

where machine name is the name or IP address of the machine hosting SAP. 

If you have multiple SAP instances on Windows machine then all instances must be installed under the same directory SAPMNT. 

On all OS, UNIX, Linux, and Windows the next directory level is SID. 

SID stands for SAP system identifier.

SAP Hardware

SAP Hardware

Hardware is an essential component of a SAP system. Hardware consists of:

•   Servers (middle tier and database tier computers)
•   Disk Storage System
•   Network Gear (routers, switches etc)
•   Take Backup Units

All of these components work together to create a healthy system. Failure of even one component could halt the whole system, costing the company millions of dollars. 

All kind of systems are available in SAP hardware marketplace, from small and medium user platforms to large and highly resilient platforms.

Some large platforms are also capable of scale on the fly to meet the changing needs. 

When making a hardware purchase decision, solutions from different vendors should be compared. 

Most solutions cannot be compared as apples to apples. E.g. one solution could support the same workload as the other system but the level of scalability, availability, and reliability offered by the two systems could differ considerably. 

Spending little more money upfront could save the company tons of dollars on monthly maintenance and downtime costs.

Server Hardware

Server hardware comes in three main categories:

•  Small
•  Medium
•  High

A server can cost from a few thousand dollars to several million. Servers vary in performance as well. Main factors influencing server performance include:

• CPUs
• Speed of CPUs
•  Amount of RAM
•  Internal server architecture
•  Support for high-speed disk operations

Servers also vary in terms of configuration flexibility and adaptability.

SAP Hardware Solution

An SAP solution may utilize severs from any of the three categories. Typically high performance servers are used at database tier, while a middle tier could utilize inexpensive servers. Some businesses choose to utilize high performance machines at all tiers. Machines could be carved up into partitions or virtual machines. While other businesses might decide to go with low end hardware across the board relying on SAP's horizontal scalability.

Propriety Platforms

Most large hardware vendors use proprietary CPU (Central Processing Units) chips in their machines. Also most large vendors support only proprietary OS (Operating System)

Examples are:

•  IBM’s PowerPC chip running AIX operating system.
•  HP’s end-of-plife PA-RISC running HP-UX operating system.
•  HP’s Itanium2-based IA64 running HP-UX operating system.

You should also explore the ability of the machine to run other operating system as well. If you seek to retire SAP then you can simply use the same box internally after deploying less expensive operating system like Linux. 

For example HP's Itanium2-based IA64 also supports Linux and Windows operating systems

X64 Platforms

Late trend is investing in x64 platforms. An x64 platform is a low cost server based on Intel or AMD CPU rather than proprietary CPU. Windows based desktops and laptops that you buy from retail stores are also x64 machines. Recently x64 machines have become very powerful and now are rivalling proprietary systems in terms of high availability and visualization options. HP and Dell are big players in this market. Sun also offers bit of a choice. One time low up front cost should be a decision making criteria. Total cost through the life time of the system should be considered while making a decision.

High Availability

High availability feature is very important for an SAP system. Even if you are incurring additional charges you should consider high availability feature for SAP. High availability is an implementation of features that ensures a certain absolute degree of operational continuity. High availability features include:

•  Redundant power supplies
•  Disk array controllers (RAID) (array of disks keeps system running even if one disk fails)
•  Support for multiple network cards

Networks should be configured in a redundant fashion as well. Using dual network switches is a good example in this regards.

Disk Subsystem Hardware

Disk subsystems are enclosures for multiple disks. Disk subsystems could be used at database tier or at middle tier. Storage Area Networks (SANs) are example of most robust and high performance disk systems. Network-attached storage (NAS) is example of lesser extent disk systems. SANs and NAS devices are marketed under three categories: low-tier, mid-tier, and high-end.

Storage for SAP

Storage used with SAP system should support redundant connectivity between the storage device and the servers connected to it. This will avoid the single point of failure

RAID

RAID (Redundant Array of Inexpensive Disks) should be configured as well. RAID is a technology that allowed computer users to achieve high levels of storage reliability from low-cost and less reliable PC-class disk-drive components. This is achieved by arranging the devices into arrays for redundancy. RAID comes in following levels:

•   Level 0
•   Level 1
•   Level 5
•   Level 10

Different levels provide various combinations of availability, cost, and performance. 

RAID 0 is the cheapest and RAID 10 is the most expensive option.