Logical system?

[Former Member]

Hi Experts.

Q1. wht is logical system and why we need to create logical system?

Q2. Wht is the diff. between message type and data type?

Cheers

Faisal

[aashish_sinha]

Hi,

Logical Systems

We define all communication in ALE as links between logical systems. A logical system is a system containing applications that are coordinated to work with one set of data. A logical system can be:

A specific client on a specific SAP system

A non-SAP system

A file-based interface

Since logical systems are the basis of all ALE configurations, the ability to define them should be restricted to as few people as possible

In the business service go to the menu Business Service --> Adapter Specific Identifiers and add the Logical System name

DATA TYPE:

smallest representation of data in XI.

A data type is an XML Schema Definition (XSD). This definition determines how the valid payload of a message will look. Data types in XML schema are only an abstract description of a structure that you can assign to elements in an XML schema definition. A message type or a fault message type that references a data type determines the name of the root element of a message.

there are 3 types of data type:

1)Built-In Type

2)Simple Type and

3)Complex Type

see here for more info

http://help.sap.com/saphelp_nw04/helpdata/en/a5/04623c4f69b712e10000000a114084/content.htm

MESSAGE TYPE:

A message type comprises a data type that describes the structure of a message.It comprises exactly one data type, which determines the content of the message to be transferred.It is identified by a name and an XML namespace. The name (together with the namespace) of a message type is located in the uppermost tag of the message to be exchanged.

see here for details

http://help.sap.com/saphelp_nw04/helpdata/en/2d/c0633c3a892251e10000000a114084/content.htm

Main difference is

data type is just a basic structure using which we build the actual message structure...

data type dont have XML namespace...

You can also refer to this thread.

Regards

Aashish Sinha

PS : reward points if helpful

[Former Member]

Hi Faisal,

Logical System is just for aliasing(giving a nick name) your Technical system. By the name of this logical system you can refer to your actual Technical system.So you can assign the logical system to a technical system.

By data type you just declare the structure for your source or target data.

Message type hold your actual data at runtime. So you assign your data type to the meg type to make it understand that it should hold data at runtime in this structure (defined in data type).

Please reward points.

---Sankar Choudhury

[former_member238007]

Hi Abdul,

Logical system is the name given to the physical system i.e technical system, Some times we can easily say in terms of SAP as an indivdual client.

every individual client in SAP can be called as an Logical system..

logical systems can be created using tcode scc4..

Business systems, which name the logical receiver independently of technical properties. For example, a business system might be a client of an SAP system

Coming to the Differince between the messagetype and to the datatype..

Datatype is the place where actual structure was developed and any changes can be made here but where as message type takes the structure of data type to the message interface as message inteface can only accept message type we cannot directly use this data type in the environment, so we need to assign the data type to the message type where message types are used in the messageinterfaces...

regards

Kishore

[Former Member]

Hi,

Logical system comes into picture whenever there is ALE communication between systems.The transaction code for creating logical sysytem is BD54.

Data type is encapsulated in message type .Message type inturn is encapsulated in message interface.

Regards,

Lokesh

PS:Reward points if useful.

[Former Member]

Hi,

A logical system is used to identify an individual client in a system, for ALE communication between SAP systems.

Creation of Logical system: TCODE : BD54

Assign a client to it

Difference bet data type and message type

Regards

Seshagiri