Jun 14, 2008

ASAP Implementation Methodology

ASAP Implementation Methodology

Overview

Any enterprise application software has to cover a broad spectrum of functionality, yet to be configured enough to meet specific requirements. SAP achieves this by ASAP methodology & R/3 Business Engineer.

AcceleratedSAP (ASAP) is SAP’s standard implementation methodology. It contains the Roadmap, a step-by step guide that incorporates experience from many years of implementing SAP. Quality checks are incorporated at end of each phase to ensure quality of deliverables and monitor critical success factors.

ASAP is delivered as a PC based package, so that an implementation project can begin prior to having an SAP R/3 system installed.

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ASAP Tools

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ASAP Roadmap

ASAP and Business Engineer have compatibility with many third party modeling tools and packages like MS Excel etc

ASAP Implementation Methodology

R/3 Business Engineer

It contains a set of configuration and implementation tools, which enable you or your consultants to define configuration SAP. It helps to implement SAP R/3 very fast. SAP has standardized the SAP implementation procedure, simplified the way fu8nctions are presented and reduced the technical complexity of implementation. The Business Engineer resides in SAP.

ASAP along with Business Engineer is suitable to

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Business professionals who need to discuss, prototype and design their Business Blueprint (enterprise model)

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IS departments of large enterprises who need to customize R/3 applications more effectively and more rapidly.

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Small and medium scale companies, who wish to implement SAP in cost-effective way.

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Consultants and SAP partners who are looking for efficient way of offering their services.

Some of the features of ASAP with Business Engineer are:

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Reduced implementation time.

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Intuitive understanding of wide range of functions offered by SAP R/3

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Process optimization using proven scenarios, processes and value chains.

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High quality installations through comprehensive procedural guidelines.

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Continuous, dynamic adjustment and optimization of SAP R/3 applications.

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The capability to copy configured areas.

ASAP Implementation Methodology

ASAP Roadmap

Phase 1: Project Preparation

Phase 2: Business Blueprint

Phase 3: Realization

Phase 4: Final Preparation

Phase 5: Go Live & Support

ASAP Implementation Methodology

Phase 1 : Project Preparation

In this phase of the ASAP Roadmap, decision-makers define clear project objectives and an efficient decision-making process.

Here Project Organization and roles are defined and implementation scope is finalized.

System landscape and Technical Requirement

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Infrastructure need (Hardware/interfaces): Available- QuickSizing Service: to be accessed via SAPNet

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System Landscape

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High level strategies for client

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Archiving strategy

Issues Database:

Issues must be resolved before phase completion ot before beginning of the next phase. The issues can be

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Unanticipated tasks

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Normal tasks that can not be completed

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External factors that need to be dealt with.

Issues database allows the project team to enter, track and report on project issues.

ASAP Implementation Methodology



Phase 2: Business Blueprint

In this phase scope of the R/3 implementation is defined & Business Blueprint is created. Business Blueprint is a detailed documentation of company’s requirements.

Various tools are used in this phase.

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AcceleratedSAP Implementation Assistant

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Question & Answer Database (Q&Adb)

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Business Process Master List (BPML)

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R/3 Structure Modeler

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Business Navigator and external modeling tools

Project Management:

Activities in this work package are:

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Conducting Status meeting for project team

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Conducting steering committee meetings

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General project management

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Addressing organizational issues relating to organizational change management.

Other activities include:

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Project Team Training

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Developing the System Environment

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Defining Organizational Structure

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Defining the Business processes

R/3 reference model can be used for

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Comparing the standard functionality with your companies own organizational requirements

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Creating documentation for the conceptual design

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Optimizing business processes

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Training the project team and users

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Writing user documentation

Question and Answer Database can be used to determine

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The Baseline Scope

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Cycle Plan

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Integration test Plan

ASAP Implementation Methodology

Phase 3: Realization

The purpose of Phase 3 is to configure the R/3 system. The configuration is carries out in two steps; baseline configuration & Final configuration.

Business Process Master List (BPML) is created in phase 2 as a report from Q&A database. It is used to identify, plan, schedule and monitor the configuration and testing of all R/3 scenarios and processes within the scope of an implementation. BPML is a representation of the R/3 business and transactions that are contained within the scope of the project. BPML is feeds all business information to all subsequent worksheets.

Implementation Guide (IMG): It is the main tool for setting the parameters to configure or ‘Customize’ R/3 during the realization phase. IMG reflect the chronological order in which the customizing activities are carried out.

The following aspects of configuration are also to be considered:

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Defining authorizations in the R/3 system

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Defining workflows

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Creating user documentation

System Manager Procedures

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Developing system test plans

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Defining service level commitment

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Establishing system administration functions

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Setting up Quality Assurance environment

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Defining the design of the productive system

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Defining system management procedures for the productive system

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Setting up the productive environment

At the end of this phase, Project Manager must check the status of deliverables for completeness and accuracy. This internal quality check should be carried out in addition to an external, independent third party Quality Audit.

Preparation for end-user training needs to be gone through and approved at and of this phase.

ASAP Implementation Methodology

Phase 4: Final Preparation

The purpose of this phase is to complete the final preparation of the R/3 system for going live. This includes testing, user training, system management and cutover activities, to finalize your readiness to go live.

In this phase the R/3 system is handed over to individual departments for productive operation. This includes preparation of end-user documentation and training the end-users. The technical environment is installed on production system & is tested. Project managers prepare plans for going live, transfer of legacy data and support at early stages.

End-user training is a critical activity for success of the project. InfoDB may be used to plan for the User Training activities. Computer Center Management System (CCMS) must be set at this time. Simulation of productive operation system & testing the same is of great important.

The test plan contains the following activities

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Testing conversion procedures and programs.

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Testing interface programs

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Conducting volume & stress testing

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Conducting final user acceptance testing

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Developing a final go-live strategy.

The Computer Aided Test Tool (CATT) can be used to automate test sequences for key business processes.

Phase 4 also provides for the testing of the disaster recovery plan for the productive environment. Disaster downtimes are verified and details on de-escalation.

ASAP Implementation Methodology



Phase 5: Go Live & Support

This phase is concerned with supporting and optimizing the operative R/3 system.

Following activities are carried out

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Production support facilities are defined.

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Validation of business processes and their configuration.

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Follow-up training for users

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Signoffs etc.

During phase 5, the first EarlyWatch session should be held, where experts from SAP analyze the system’s technical infrastructure. The aim is to ensure the system functions as smooth as possible.

Version upgrades should be planned whenever found necessary. AcceleratedSAP contains a continuous roadmap, with standard activities necessary after implementation. The tasks in that structure provide solutions for all known types of continuous change: Business changes, technology changes or changes in user community.

Jun 13, 2008

SAP Implementation Life cycle.

A full life cycle implementation for a company means that suppose a company want to Implement SAP in their organization then the process start form requirement gathering, analysis, solution design, mapping, Implementing.

For this entire development there are some phases like.

1.project preparation.
2.Business blue print.
3.Realization.
4.Final preparation
5.Go live

These are all the phases which we have to follow while implementing SAP to a specific company. This we can also called as ASAP methodology.

How to Show Full Life Cycle in your Resume

In your resume you have to explain two things

1. what your team have done in this project
2. what is your role in this project?

What your team have done?
In this you have to explain what your company have done and have to give then details of the company along with the SAP Version Like
• Company Name
• SAP Version
• Oracle Version
• Your team size
• Your Team leader

What is your role in this project?
In this you have to give the brief description what is your role in this project like
On which modules you working and on which Transaction you are working.

Jun 12, 2008

ABAP EVENTS

Enterprise resource planning

Enterprise resource planning

Enterprise Resource Planning systems (ERPs) integrate (or attempt to integrate) all data and processes of an organization into a unified system. A typical ERP system will use multiple components of computer software and hardware to achieve the integration. A key ingredient of most ERP systems is the use of a unified database to store data for the various system modules.

Origin of the term

The term ERP originally implied systems designed to plan the use of enterprise-wide resources. Although the acronym ERP originated in the manufacturing environment, today's use of the term ERP systems has much broader scope. ERP systems typically attempt to cover all basic functions of an organization, regardless of the organization's business or charter. Business, non-profit organizations, non governmental organizations, governments, and other large entities utilize ERP systems.

Additionally, it may be noted that to be considered an ERP system, a software package generally would only need to provide functionality in a single package that would normally be covered by two or more systems. Technically, a software package that provides both payroll and accounting functions would be considered an ERP software package.

However, the term is typically reserved for larger, more broadly based applications. The introduction of an ERP system to replace two or more independent applications eliminates the need for external interfaces previously required between systems, and provides additional benefits that range from standardization and lower maintenance (one system instead of two or more) to easier and/or greater reporting capabilities (as all data is typically kept in one database).

Examples of modules in an ERP which formerly would have been stand-alone applications include: Manufacturing, Supply Chain, Financials, Customer Relationship Management (CRM), Human Resources, and Warehouse Management.

Overview

Some organizations - typically those with sufficient in-house IT skills to integrate multiple software products - choose to implement only portions of an ERP system and develop an external interface to other ERP or stand-alone systems for their other application needs. For instance, the PeopleSoft HRMS and Financials systems may be perceived to be better than SAP's HRMS solution. And likewise, some may perceive SAP's manufacturing and CRM systems as better than PeopleSoft's equivalents. In this case these organizations may justify the purchase of an ERP system, but choose to purchase the PeopleSoft HRMS and Financials modules from Oracle, and their remaining applications from SAP.[citation needed]

This is very common in the retail sector[citation needed], where even a mid-sized retailer will have a discrete Point-of-Sale (POS) product and financials application, then a series of specialized applications to handle business requirements such as warehouse management, staff roistering, merchandising and logistics.

Ideally, ERP delivers a single database that contains all data for the software modules, which would include:

Manufacturing

Engineering, Bills of Material, Scheduling, Capacity, Workflow Management, Quality Control, Cost Management, Manufacturing Process, Manufacturing Projects, Manufacturing Flow

Supply Chain Management

Inventory, Order Entry, Purchasing, Product Configuration, Supply Chain Planning, Supplier Scheduling, Inspection of goods, Claim Processing, Commission Calculation

Financials

General Ledger, Cash Management, Accounts Payable, Accounts Receivable, Fixed Assets

Projects

Costing, Billing, Time and Expense, Activity Management

Human Resources

Human Resources, Payroll, Training, Time & Attendance, Benefits

Customer Relationship Management

Sales and Marketing, Commissions, Service, Customer Contact and Call Center support

Data Warehouse

and various Self-Service interfaces for Customers, Suppliers, and Employees

Enterprise Resource Planning is a term originally derived from manufacturing resource planning (MRP II) that followed material requirements planning (MRP). MRP evolved into ERP when "routings" became major part of the software architecture and a company's capacity planning activity also became a part of the standard software activity. ERP systems typically handle the manufacturing, logistics, distribution, inventory, shipping, invoicing, and accounting for a company. Enterprise Resource Planning or ERP software can aid in the control of many business activities, like sales, marketing, delivery, billing, production, inventory management, quality management, and human resource management.

ERPs are often incorrectly called back office systems indicating that customers and the general public are not directly involved. This is contrasted with front office systems like customer relationship management (CRM) systems that deal directly with the customers, or the eBusiness systems such as eCommerce, eGovernment, eTelecom, and eFinance, or supplier relationship management (SRM) systems.

ERPs are cross-functional and enterprise wide. All functional departments that are involved in operations or production are integrated in one system. In addition to manufacturing, warehousing, logistics, and Information Technology, this would include accounting, human resources, marketing, and strategic management.

ERP II means open ERP architecture of components. The older, monolithic ERP systems became component oriented.

EAS - Enterprise Application Suite is a new name for formerly developed ERP systems which include (almost) all segments of business, using ordinary Internet browsers as thin clients.

Before

Prior to the concept of ERP systems, departments within an organization (for example, the Human Resources (HR) department, the Payroll (PR) department, and the Financials department) would have their own computer systems. The HR computer system (Often called HRMS or HRIS) would typically contain information on the department, reporting structure, and personal details of employees. The PR department would typically calculate and store paycheck information. The Financials department would typically store financial transactions for the organization. Each system would have to rely on a set of common data to communicate with each other. For the HRIS to send salary information to the PR system, an employee number would need to be assigned and remain static between the two systems to accurately identify an employee. The Financials system was not interested in the employee level data, but only the payouts made by the PR systems, such as the Tax payments to various authorities, payments for employee benefits to providers, and so on. This provided complications. For instance, a person could not be paid in the Payroll system without an employee No.

After

ERP software, among other things, combined the data of formerly separate applications. This made the worry of keeping numbers in synchronization across multiple systems disappear. It standardized and reduced the number of software specialties required within larger organizations.

Best Practices

Best Practices were also a benefit of implementing an ERP system. When implementing an ERP system, organizations essentially had to choose between customizing the software or modifying their business processes to the "Best Practice" functionality delivered in the vanilla version of the software.

Typically, the delivery of best practice applies more usefully to large organizations and especially where there is a compliance requirement such as IFRS, Sarbanes-Oxley or Basel II, or where the process is a commodity such as electronic funds transfer. This is because the procedure of capturing and reporting legislative or commodity content can be readily codified within the ERP software, and then replicated with confidence across multiple businesses who have the same business requirement.

Where such a compliance or commodity requirement does not underpin the business process, it can be argued that determining and applying a best practice actually erodes competitive advantage by homogenizing the business compared to everyone else in their industry sector.

Evidence for this can be seen within EDI, where the concept of best practice, even with decades of effort remains elusive. A large retailer, for example, wants EDI plus some minor tweak that they perceive puts them ahead of their competition. Mid-market companies adopting ERP often take the vanilla version and spend half as much as the license cost doing customizations that deliver their competitive edge. In this way they actively work against best practice because they perceive that the way they operate is best practice, irrespective of what anyone else is doing.

Implementation

Because of their wide scope of application within a business, ERP software systems are typically complex and usually impose significant changes on staff work practices. Implementing ERP software is typically not an "in-house" skill, so even smaller projects are more cost effective if specialist ERP implementation consultants are employed. The length of time to implement an ERP system depends on the size of the business, the scope of the change and willingness of the customer to take ownership for the project. A small project (e.g., a company of less than 100 staff) may be planned and delivered within 3 months; however, a large, multi-site or multi-country implementation may take years.

The most important aspect of any ERP implementation is that the company who has purchased the ERP product takes ownership of the project.

To implement ERP systems, companies often seek the help of an ERP vendor or of third-party consulting companies. These firms typically provide three areas of professional services: Consulting, Customization and Support.

Consulting Services

The Consulting team is typically responsible for your initial ERP implementation and subsequent delivery of work to tailor the system beyond "go live". Typically such tailoring includes additional product training; creation of process triggers and workflow; specialist advice to improve how the ERP is used in the business; system optimization; and assistance writing reports, complex data extracts or implementing Business Intelligence.

The consulting team are also responsible for planning and jointly testing the implementation. This is a critical part of the project, and one that is often overlooked.

Consulting for a large ERP project involves three levels: systems architecture, business process consulting (primarily re-engineering) and technical consulting (primarily programming and tool configuration activity). A systems architect designs the overall dataflow for the enterprise including the future dataflow plan. A business consultant studies an organization's current business processes and matches them to the corresponding processes in the ERP system, thus 'configuring' the ERP system to the organization's needs. Technical consulting often involves programming. Most ERP vendors allow modification of their software to suit the business needs of their customer.

For most mid-sized companies, the cost of the implementation will range from around the list price of the ERP user licenses to up to twice this amount (depending on the level of customization required). Large companies, and especially those with multiple sites or countries, will often spend considerably more on the implementation than the cost of the user licenses -- three to five times more is not uncommon for a multi-site implementation.

Customization Services

Customization is the process of extending or changing how the system works by writing new user interfaces and underlying application code. Such customizations typically reflect local work practices that are not currently in the core routines of the ERP system software.

Examples of such code include early adopter features (e.g., mobility interfaces were uncommon a few years ago and were typically customized) or interfacing to third party applications (this is 'bread and butter' customization for larger implementations as there are typically dozens of ancillary systems that the core ERP software has to interact with). The Professional Services team is also involved during ERP upgrades to ensure that customizations are compatible with the new release. In some cases the functionality delivered via a previous customization may have been subsequently incorporated into the core routines of the ERP software, allowing customers to revert back to standard product and retire the customization completely.

Customizing an ERP package can be very expensive and complicated, because many ERP packages are not designed to support customization, so most businesses implement the best practices embedded in the acquired ERP system. Some ERP packages are very generic in their reports and inquiries, such that customization is expected in every implementation. It is important to recognize that for these packages it often makes sense to buy third party plug-ins that interface well with your ERP software rather than reinventing the wheel.

Customization work is usually undertaken as bespoke software development on a time and materials basis. Because of the specialist nature of the customization and the 'one off' aspect of the work, it is common to pay in the order of $200 per hour for this work. Also, in many cases the work delivered as customization is not covered by the ERP vendors Maintenance Agreement, so while there is typically a 90-day warranty against software faults in the custom code, there is no obligation on the ERP vendor to warrant that the code works with the next upgrade or point release of the core product.

One often neglected aspect of customization is the associated documentation. While it can seem like a considerable -- and expensive -- overhead to the customization project, it is critical that someone is responsible for the creation and user testing of the documentation. Without the description on how to use the customization, the effort is largely wasted as it becomes difficult to train new staff in the work practice that the customization delivers.

Maintenance and Support Services

Once your system has been implemented, the consulting company will typically enter into a Support Agreement to assist your staff keep the ERP software running in an optimal way. To minimize additional costs and provide more realism into the needs of the units to be affected by ERP (as an added service to customers), the option of creating a committee headed by the consultant using participative management approach during the design stage with the client's heads of departments(no substitutes allowed) to be affected by the changes in ERPS to provide hands on management control requirements planning. This would allow direct long term projections into the client's needs, thus minimizing future conversion patches (at least for the 1st 5 years operation unless there is a corporate-wide organizational structural change involving operational systems)on a more dedicated approach to initial conversion.

A Maintenance Agreement typically provides you rights to all current version patches, and both minor and major releases, and will most likely allow your staff to raise support calls. While there is no standard cost for this type of agreement, they are typically between 15% and 20% of the list price of the ERP user licenses.

Advantages

In the absence of an ERP system, a large manufacturer may find itself with many software applications that do not talk to each other and do not effectively interface. Tasks that need to interface with one another may involve:

Change how a product is made, in the engineering details, and that is how it will now be made. Effective dates can be used to control when the switch over will occur from an old version to the next one, both the date that some ingredients go into effect, and date that some are discontinued. Part of the change can include labeling to identify version numbers.

Computer security is included within an ERP to protect against both outsider crime, such as industrial espionage, and insider crime, such as embezzlement. A data tampering scenario might involve a terrorist altering a Bill of Materials so as to put poison in food products, or other sabotage. ERP security helps to prevent abuse as well.

Disadvantages

Many problems organizations have with ERP systems are due to inadequate investment in ongoing training for involved personnel, including those implementing and testing changes, as well as a lack of corporate policy protecting the integrity of the data in the ERP systems and how it is used.

Limitations of ERP include:

Success depends on the skill and experience of the workforce, including training about how to make the system work correctly. Many companies cut costs by cutting training budgets. Privately owned small enterprises are often undercapitalized, meaning their ERP system is often operated by personnel with inadequate education in ERP in general, such as APICS foundations, and in the particular ERP vendor package being used.

  • Personnel turnover; companies can employ new managers lacking education in the company's ERP system, proposing changes in business practices that are out of synchronization with the best utilization of the company's selected ERP.
  • Customization of the ERP software is limited. Some customization may involve changing of the ERP software structure which is usually not allowed.
  • Re-engineering of business processes to fit the "industry standard" prescribed by the ERP system may lead to a loss of competitive advantage.
  • ERP systems can be very expensive to install often ranging from 30,000 to 500,000,000 for multinational companies.
  • ERP vendors can charge sums of money for annual license renewal that is unrelated to the size of the company using the ERP or its profitability.
  • Technical support personnel often give replies to callers that are inappropriate for the caller's corporate structure. Computer security concerns arise, for example when telling a non-programmer how to change a database on the fly, at a company that requires an audit trail of changes so as to meet some regulatory standards.
  • ERPs are often seen as too rigid and too difficult to adapt to the specific workflow and business process of some companies—this is cited as one of the main causes of their failure.
  • Systems can be difficult to use.
  • The system can suffer from the "weakest link" problem—an inefficiency in one department or at one of the partners may affect other participants.
  • Many of the integrated links need high accuracy in other applications to work effectively. A company can achieve minimum standards, then over time "dirty data" will reduce the reliability of some applications.
  • Once a system is established, switching costs are very high for any one of the partners (reducing flexibility and strategic control at the corporate level).
  • The blurring of company boundaries can cause problems in accountability, lines of responsibility, and employee morale.
  • Resistance in sharing sensitive internal information between departments can reduce the effectiveness of the software.
  • There are frequent compatibility problems with the various legacy systems of the partners.
  • The system may be over-engineered relative to the actual needs of the customer.

List of ERP vendors

A list of Enterprise resource planning (ERP) vendors.

ERP vendors by revenue

The largest vendors wordwide in 2005 according to Gartner Dataquest:

Market share 2005 according to Gartner Dataquest[1]

# ↓

Vendor ↓

Revenue
(million $) ↓

Market share
(%) ↓

1

SAP

4726

28.7

2

Oracle Applications

1674

10.2

3

The Sage Group

1221

7.4

4

Microsoft Dynamics

616

3.7

5

SSA Global Technologies[2]

464

2.8

Other vendors of popular ERP software include (sorted roughly according to worldwide ERP related revenue):

Vendor ↓

Revenue[3]
(Native currency) ↓

Revenue[4]
(million $) ↓

Year ↓

SAP

9.4 billion EUR

12401.4

2006

Oracle Applications

14.38 billion USD

14380.0

2006

Infor Global Solutions

2.1 billion USD

2100.0

unknown

The Sage Group

935.6 million GBP

1832.0

2006

Microsoft Dynamics (Formerly Microsoft Business Solutions)

44.2 billion USD

44200.0

2006

Unit 4 Agresso

352.6 million EUR

465.2

2005

Lawson Software

390.776 million USD

390.8

2006

Epicor

384.1 million USD

384.1

2006

Visma

1,907 million NOK

305.5

2005

Industrial and Financial Systems

288 million USD

288.0

2005

QAD

225 million USD

225.0

2006

Ramco Systems

2,648 million INR

60.1

2006

NetSuite

40 million USD

40.0

2004

SIV.AG

14.2 million EUR

18.7

unknown

List of ERP software packages

Free and Open Source ERP software

(sorted alphabetically)

Proprietary ERP software

What is 3- and n-tier architecture


What is 3- and n-tier architecture


N-Tier Architecture:

N-tier architecture has become a buzzword among serious developers. Simply put, n-tier architecture means carefully separating your application into any number of logical, functional layers. For example, you may
separate your your data, your business logic, and your presentation. This allows your application to be better organized and maintained. It also allows your application to be deployed in a wider variety of ways.

Developing an application using n-tier architecture usually (not always) takes more time, so it is important to identify which level n-tier to use
Easy installation, simple upgrades, and excellent security are only a few of the benefits that come when an application is divided into multiple layers.
As an example, imagine this diagram represents a company with users accessing the application from the office, home, and remotely, using wireless devices. If the company wants to change their application (e.g. use a more powerful database, or add some business logic), they can do so with little effort.
Client-tier-
Is responsible for the presentation of data, receiving user events and controlling the user interface. The actual business logic (e.g. calculating added value tax) has been moved to an application-server. Today, Java-applets offer an alternative to traditionally written PC-applications. See our Internet-page for further information.
Application-server-tier-
application server provides exposes business logic for client applications through various protocols.
Furthermore, the term "component" is also to be found here. Today the term pre-dominantly describes visual components on the client-side. In the non-visual area of the system, components on the server-side can be defined as configurable objects, which can be put together to form new application processes.

Data-server-tier-
This tier is responsible for data storage. Besides the widespread relational database systems, existing legacy systems databases are often reused here.
It is important to note that boundaries between tiers are logical. It is quite easily possible to run all three tiers on one and the same (physical) machine. The main importance is that the system is neatly structured, and that there is a well planned definition of the software boundaries between the different tiers.


Clear Explanation for 2 and 3 –tier architectures with examples:

Let's suppose I'm going to write a piece of software that students at a school can use to find out what their current grade is in all their classes. I structure the program so that a database of grades resides on the server, and the application resides on the client (the computer the student is physically interacting with).

When the student wants to know his grades, he manipulates my program (by clicking buttons, menu options, etc). The program fires off a query to the database, and the database responds with all the student's grades. Now my application uses all this data to calculate the student's grade, and displays it for him.

This is an example of a 2-tier architecture. The two tiers are:

1. Data server: the database serves up data based on SQL queries submitted by the application.
2. Client application: the application on the client computer consumes the data and presents it in a readable format to the student.

Now this architecture is fine.If you've got a school with 50 students. But suppose the school has 10,000 students.Now we've got a problem. Why?

Because every time a student queries the client application, the data server has to serve up large queries for the client application to manipulate. This is an enormous drain on network resources.

So what do we do? We create a 3-tier architecture by inserting another program at the server level. We call this the server application. Now the client application no longer directly queries the database; it queries the server application, which in turn queries the data server.

What is the advantage to this? Well, now when the student wants to know his final grade, the following happens:

1. The student asks the client application.
2. The client application asks the server application.
3. The server application queries the data server.
4. The data server serves up a recordset with all the student's grades.
5. The server application does all the calculations to determine the grade.
6. The server application serves up the final grade to the client application.
7. The client application displays the final grade for the student.

It's a much longer process on paper, but in reality it's much faster. Why? Notice step 6. Instead of serving up an entire recordset of grades, which has to be passed over a network, the server application is serving up a single number, which is a tiny amount of network traffic in comparison.

There are other advantages to the 3-tier architecture, but that at least gives you a general idea of how it works.

Incidentally, this website is a 3-tier application. The client application is your web browser. The server application is the ASP code, which queries the database (the third tier) for the question-and-answer you requested

Apr 1, 2008

FAQ on DATA DICTIONARY

ABAP Dictionary

a.. What types of objects can be created in the ABAP Dictionary?

b.. What types of tables can be created in the ABAP Dictionary?
c.. Which field differentiates a table from client-dependent and client-independent?
d.. What is the difference between Pooled tables and Cluster tables?
e.. What is the difference between Database tables and Views?
f.. What are the different types of Views?
g.. Can I use all the views in the ABAP program ?
h.. What is Table Maintenance Generator?
i.. What is One step, two step in Table Maintenance Generator?
j.. How do you activate the database table after making changes to it?
k.. In which table are the programs stored in?
l.. I have recently added a few fields to a custom table. But I don't get these fields in the table maintenance program?
m.. What is the difference between INSERT and MODIFY?
n.. How do I create index on a database table?
o.. What is the difference between Check Table and Value Table?
p.. When Value table becomes check table?
q.. What is the difference between Domain and Data Elements?
r.. When I create new entries in the table the field values are always in Uppercase. How do I get the data with mixed case?
s.. What is the need of reference table and reference field in Currency/Quantity fields?
t.. Where to find the table of tables?
u.. How to add new fields in standard table ?

Answers...

What types of objects can be created in the ABAP Dictionary?
Tables
Views
Data Elements
Structures
Table Types
Type Groups
Domains
Search Helps
Lock Objects


What types of tables can be created in the ABAP Dictionary?
Transparent Tables
Pooled and Clustered Tables


Which field differentiates a table from client-dependent and client-independent?
The MANDT field of the table specifies whether the table is client independent or not. Client-dependent tables contains MANDT column and are client specific. Client Independent tables do not have MANDT columan and can be accessed from any client.


What is the difference between Pooled tables and Cluster tables?
Cluster tables and Pooled tables have many to one relationship with the underlying database.

A table pool corresponds to a table in the database in which all records from the pooled tables assigned to it are stored.
Several logical data records from different cluster tables can be stored together in one physical record in a table cluster.

a.. A pooled table cannot have the name having more than 10 characters.
b.. All the key fields of the pooled table must be of character data type.
c.. In pooled tables, the maximum length of the key field/data fields should not exceed the length of varkey/vardata of the pool respectively.
a.. In cluster table the records having the same key are stored in a single key in the cluster.
b.. If there is an overflow of the data records a continuation record is created with the same table key.

What is the difference between Database tables and Views?
The Table has a physical storage of data whereas views do not have physical storage of data.

The view is derived from one or more tables which is created only with the required fields from the database table(s). It can also be created with table inner joins and specifying conditions for data retrieval.

What are the different types of Views?
a.. Projection view - Just retrieves some fields from a single table.
b.. Help View - This is used for search help.
c.. Database View - This is inner join view of one or more tables
d.. Maintenance View - Helps in creating maintaining data of the application object. The data can be distributed among several tables.
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Can I use all the views in the ABAP program ?
No. You can use only projection view or database view in your ABAP program.

What is Table Maintenance Generator?
The Table Maintenance Generator is used to create table maintenance program to add, modify or delete records in the database table. This can be accessed using transaction SE54 or in SE11 using the menu Utilities->Table Maintenance Generator.

What is One step, two step in Table Maintenance Generator?
This specifies the screens to be created in the Table Maintenance Program.

Single step: Only overview screen is created i.e. the Table Maintenance Program will have only one screen where you can add, delete or edit records.

Two step: Two screens namely the overview screen and Single screen are created. The user can see the key fields in the first screen and can further go on to edit further details.

How do you activate the database table after making changes to it?
After making changes to the table, inorder to reflect the changes go to transaction SE14 and Choose Edit and then choose Activate and Adjust Database.

OR

You can directly activate it from the SE11.

In which table are the programs stored in?
The programs are stored in the table TADIR and the development class packages in TDEVC.

I have recently added a few fields to a custom table. But I don't get these fields in the table maintenance program?
You have to delete and recreate your own existing table maintenance program to see your new fields.

What is the difference between INSERT and MODIFY?
Whenever you need to create new records in the database table use INSERT. Whenever using INSERT be sure that a duplicate entry having the same values for the primary key fields are not present. Else it may throw a dump.

When you use MODIFY it makes a check for the matching key field values. If present it modifies the matching record, else it creates a new record in the database table.

How do I create index on a database table?
Go to transaction SE11, open your database table. Choose the menu, Goto->Indexes to create index. Give your index name and choose the fields of the table. Be careful, an additional index may vanish with the next upgrade or hotpackage.

What is the difference between Check Table and Value Table?
The Check Table is the dependent table to which the relationship is defined using foreign keys. The contents of the check table field are shown in the input help for the referenced field.

The Value table is the table attached to a field at the domain level, where the entry to the field can be only from the value table. They are not used in the Input Help.

When Value table becomes check table?
while establishing foriegn key relation between check table and foriegn key table if at the domain level value table is provided then the system will prapose that value table as check table if you accept this prposal then value table will becomes check table.

What is the difference between Domain and Data Elements?
The Domain specifies the Technical attributes of the field such as the data type, length and the value range.

The data element is an elementary type defining the description/text for the field when displaying on the screen and Parameter ID.

When I create new entries in the table the field values are always in Uppercase. How do I get the data with mixed case?
The reason for this is that the Domain for the field in the table might have Lowercase checkbox unchecked. Check the Lowercase checkbox to preserve the case of your data.

What is the need of reference table and reference field in Currency/Quantity fields?
The reference table and reference field are the fields which specify the currency key or Unit of Measure. Suppose if the user specifies a currency amount say 1000$, the currency amount field would indicate the amount 1000 and the currency key indicates that the currency specified is in Dollars.

Where to find the table of tables?
See forum thread:
DD02L and DD02T for short text

How to add new fields in standard table ?
Create Z-Structure with the fields needed and append the structure to the standard table by using the option append structure within table display

we can enhance the standard tables by using Append structures and customizing includes.

Append structures allow you to attach fields to a table without actually having to modify the table itself. Table enhancements using append structures therefore do not have to be planned by SAP developers. An append structure can only belong to exactly one table.
In contrast, CI_includes allow you to use the same structure in multiple tables. The include statement must already exist in the SAP table or structure. Table enhancements using CI_includes do, however, have to be planned by SAP developers

How to change Transport request from Released to Modifiable

Step 1: Go to SE38 – Execute Program RDDIT076.  Step 2: Give your released requests number and execute again. Step 3: After executing, yo...