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LUW

Former Member
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HI

what is this ? and explain me the concept

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Former Member
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Logical Unit of Work (LUW)

A Logical Unit of Work (LUW or database transaction) is an inseparable sequence of database operations which must be executed either in its entirety or not at all. For the database system, it thus constitutes a unit.

LUWs help to guarantee database integrity. When an LUW has been successfully concluded, the database is once again in a correct state. If, however, an error occurs within an LUW, all database changes made since the beginning of the LUW are canceled and the database is then in the same state as before the LUW started.

An LUW begins

each time you start a transaction

when the database changes of the previous LUW have been confirmed (database commit) or

when the database changes of the previous LUW have been cancelled (database rollback)

An LUW ends

when the database changes have been confirmed (database commit) or

when the database changes have been canceled (database rollback)

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former_member386202
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Hi,

LUW ( Logical unit of work ) is spam of time during which any database must update performed.

Regards,

Prashant

Message was edited by:

Prashant Patil

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Former Member
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Hi sandhya mehar,

What is LUW?

Logical Unit of Work

Different types of LUWs. What r they?

Two types of LUW are:

1)DB LUW - A database LUW is the mechanism used by the database to ensure that its data is always consistent. A database LUW

is an inseparable sequence of database operations that ends with a database commit. The database LUW is either fully executed

by the database system or not at all. Once a database LUW has been successfully executed, the database will be in a

consistent state. If an error occurs within a database LUW, all of the database changes since the beginning of the database

LUW are reversed. This leaves the database in the state it had before the transaction started.

2)SAP LUW - A logical unit consisting of dialog steps, whose changes are written to the database in a single database LUW is

called an SAP LUW. Unlike a database LUW, an SAP LUW can span several dialog steps, and be executed using a series of

different work processes.

What is LUW or Data base Transaction ?

A “LUW”(logical unit of work) is the span of time during which any database updates must be performed in an “all or nothing”

manner .Either they are all performed (committed),or they are all thrown away (rolled back).In the ABAP/4 world , LUWs and

Transactions can have several meanings:

LUW (or “database LUW” or “database transaction”)

This is the set of updates terminated by a database commit. A LUW lasts, at most, from one screen change to the next (because

the SAP system triggers database commits automatically at every screen change).

What is SAP LUW or Update Transaction?

Update transaction (or “SAP LUW”)

This is a set of updates terminated by an ABAP/4 commit. A SAP LUW may last much longer than a database LUW, since most

update processing extends over multiple transaction screens. The programmer terminates an update transaction by issuing a

COMMIT WORK statement.

-Transactions run with a separate SAP LUW

-Reports run with a separate SAP LUW.

-Dialog modules run in the same SAP LUW as the caller

-Function modules run in the same SAP LUW as the caller.

The only exceptions to the above rules are function modules called with IN UPDATE TASK (V2 function only) or IN BACKGROUND

TASK (ALE applications). These always run in their own (separate) update transactions.

SAP LUW

http://help.sap.com/saphelp_nw04/helpdata/en/41/7af4bfa79e11d1950f0000e82de14a/content.htm

Features of the Update

http://help.sap.com/saphelp_nw04s/helpdata/en/e5/de86d835cd11d3acb00000e83539c3/content.htm

Check this thread for further details on LUW

cheers!

gyanaraj

****Pls reward points if u find this helpful