Regarding synchronous update in session method

[Former Member]

Hi,

can you explain sap luw concept and what is synchronous update and asynochronous update in bdc and link with syn update .

alreay i search in sdn i did't get exact answer..............

Regards,

Madhu

[RaymondGiuseppi]

do a lttle search or read [Update Techniques|http://help.sap.com/saphelp_nw04/helpdata/EN/41/7af4cba79e11d1950f0000e82de14a/frameset.htm] at help.sap.com

Regards,

Raymond

[manubhutani]

Hi

In BDC, if you are using synchronous method, it means that before actual database update takes place,

ur bdc will go to next transaction(next record of transaction)

but in synchronous method, until and unless currect transaction is executed(database update takes place)

it will not go to next transaction(next record of transaction)

let me know if you have any questions.

Regards

Manu

[dhirendra_pandit]

Hi Madhu,

Synchronous calls are slower but should be used for transactions that are updating the database because control is not passed back to the program until a successful database commit (or rollback) has been executed.Synchronous calls will set the return code (sy-subrc) if an error is encountered. There are actually two synchrounous update modes:

1. 'S', Synchronous update mode makes database entries describing the updates to be done and an update task (potentially running on a different computer) reads those database entries, does the update, and then deletes the entries describing the update task.

2. 'L', Local update mode describes the updates to be done in the memory of the current process. No entries are made in and then deleted from the database describing the update task.

synchonous update: is used to no transaction is stored until

the previous transaction has been written into the sap databse.

Asynchronous calls are the default if the UPDATE parameter is not specified. Asynchronous calls do not effect the return code (sy-subrc).

asynchonous: is used to the program is need not wait for the

previous transaction . any kind of transaction is stored

into the database.