Regarding transaction updates

[ravindar dayachand]

How to maintain the JDBC call from java end

I make DB update query. Based on the return value it is confirmed whether the DB is updated or not.
Now i have a scenario where i make a update query and before the value is returned the db is physically disconnected how is this tracked, i mean i have updated the db and i dont have a return value on my db is updated or not how to handle such scenario.

Please help me with this question

[Kumar Raja]

ravindar dayachand wrote:How to maintain the JDBC call from java end

I make DB update query. Based on the return value it is confirmed whether the DB is updated or not.
Now i have a scenario where i make a update query and before the value is returned the db is physically disconnected how is this tracked, i mean i have updated the db and i dont have a return value on my db is updated or not how to handle such scenario.

Please help me with this question

Carefully choosing the transaction demarcation would be helpful here. For eg, by enclosing your JDBC call and examining the response in one single transaction, could help you determine if the operation was successful or not. In the case of DB connection lost, most probably you would end up wth an exception and that is an indication for your rollback.

[ravindar dayachand]

Thanks for the reply

But how could i demark in the below case

1 case :I want to update a account my query is succesfully executed and commited, while returning the successful message DB is disconnected

2 case :i update a account and i recieve a succesful message and then i run the commit statement but while returning the sucessfull comitted status the DB is disconnected.

How will i demark in these cases.

And regarding exception, what if the exception is throw after commit how would i know whether it is committed or rollback how to handle this scenario.I cannot think it as a rollback as the exception may be thrown after a succesful commit and before we recieve the status.

[Kumar Raja]

ravindar dayachand wrote:Thanks for the reply

But how could i demark in the below case

1 case :I want to update a account my query is succesfully executed and commited, while returning the successful message DB is disconnected

2 case :i update a account and i recieve a succesful message and then i run the commit statement but while returning the sucessfull comitted status the DB is disconnected.

How will i demark in these cases.

And regarding exception, what if the exception is throw after commit how would i know whether it is committed or rollback how to handle this scenario.I cannot think it as a rollback as the exception may be thrown after a succesful commit and before we recieve the status.

Hmm, this is a quite interesting scenario and my suggestion below may not be a good one, but still I will put it forward. I wish some one in this forum could validate that and advice. I would be more curious to see if some one could contradict it and advise a better solution.

Case 1/Case 2

   
Transaction Begin
  try{
     Perform Update // The return of this process is essentially your response. 
  }
  catch Exception{
   rollback 
  }
   finally{
           try
                   check the response and perform commit or rollback
                   Transaction close // if transaction is already not closed, close it here.
           catch exception while commiting /rollback/transaction close/DB connection lost
                throw exception. //You need to essentially rollback the transaction.... 
   }