Help with Oracle Streams. How to uniquely identify LCRs in queue?

Question

We are using strems for data replication in our shop.
When an error occours in our processing procedures, the LCR is moved to the error queue.
The problem we are facing is we don't know how to uniquely identify LCRs in that queue, so we can run them again when we think the error is corrected.
LCRs contain SCN, but as I understand it, the SCN is not unique.
What is the easy way to keep track of LCRs? Any information is helpful.
Thanks

Answer 1

Hi,
When you correct the data,you would have to execute the failed transaction in order.
To see what information the apply process has tried to apply, you have to print that LCR. Depending on the size (MESSAGE_COUNT) of the transaction that has failed, it could be interesting to print the whole transaction or a single LCR.
To do this print you can make use of procedures print_transaction, print_errors, print_lcr and print_any documented on :
Oracle Streams Concepts and Administration
  Chapter - Monitoring Streams Apply Processes
     Section - Displaying Detailed Information About Apply Errors
These procedures are also available through Note 405541.1 - Procedure to Print LCRs
To print the whole transaction, you can use print_transaction procedure, to print the error on the error queue you can use procedure print_errors and to print a single_transaction you can do it as follows:
SET SERVEROUTPUT ON;
DECLARE
   lcr SYS.AnyData;
BEGIN
    lcr := DBMS_APPLY_ADM.GET_ERROR_MESSAGE
                (<MESSAGE_NUMBER>, <LOCAL_TRANSACTION_ID>);
    print_lcr(lcr);
END;
Thanks