Trail file management has been made so much easier in GoldenGate 23ai!
We can do the following very easily in GoldenGate 23ai using the WebUI:
- Download Trail Files
- Archive Trail Files
- Delete Trail Files
If we want to analyze a particular trail file to maybe investigate some issue, in GoldenGate Cloud Services we had to take a manual backup of the whole deployment and then download the deployment backup to a local disk and extract the whole backup to get to the /u02/Deployment/var/lib/data directory to find a particular trail file.
Now in 23ai we can very easily just download a single trail file or maybe a range of trail files directly from within the GoldenGate 23ai WebUI.
Note the menu option Trails.
We get to a lot of information about the trail file like the producer of the trail file which is the Extract process as well as the consumer of the trail file – the Distribution Path which accesses the trail file and transmits it over the network to the ultimate consumer of the trail file which is the Replicat process.
Download a range of trail files.
Once the trail files have been downloaded, we can use logdump utility to open and examine the relevant trail file.
One of the issues related to tables with CLOB columns and GoldenGate is related to the fact that Oracle database does not log the before image of LOB records in the redo log files.
We found a case where the replication was from Oracle source to Big Data avro files. If the CLOB column in the table was not part of an UPDATE statement, then the avro file had null values for the CLOB columns.
Let us have a look at this scenario and how we overcome this issue with CLOB columns via the GoldenGate Extract parameter GETBEFORECOLS.
The scenario is that we issue first an INSERT statement followed by an UPDATE statement – but the UPDATE statement does not directly include the CLOB column in the table.
After we download the required trail file via the GoldenGate 23ai WebUI, we can use logdump utility to open the trail file.
We do not see the CLOB column contents shown in the trail file.
We now make a change to the Extract parameter file – note the contents of the parameter file.
Now we open the trail file after performing the similar UPDATE (excluding the CLOB column) – but we see that the trail file now contains the contents of the DESCRIPTION column which is a CLOB column : “This is the first INSERT”.
