IBM Connections content missing after migration

IBM Connections content missing after migration


I`m in the middle of migrating an IBM Connections 5.0 CR3 environment to 6.0 CR3.

Having done the test migration, the customer called me with the information that some content is missing in the community description of several communities – worst case that can happen 🙁

Old environment:

The description is full of links videos…

Now the result after migrating the data using the dbt approach:

The whole middle part is missing…! What happened?

The community description is stored as HTML in a CLOB within the table “COMMUNITY” – SNCOMM Schema. The column is called DESCRIPTIONEX.

So the source html in the CLOB looked like this:


The target html data:


–> The html is totally messed up… The <table> definitions are not correctly wrapped.

How can you solve this? Well I thought about using db backup / restore to not have any dependancies on the tight projects time line. A colleague of mine told me about a similar case, where they then adjusted the following parameter in the applications xml dbt transfer files:

streamBufferSize / progressiveStreaming … Meant as performance optimization it seems that activating materialization of the CLOB objects solves the issue…

When progressive streaming is enabled, you can control when the JDBC driver materializes LOBs with the streamBufferSize property. If a LOB or XML object is less than or equal to the streamBufferSize value, the object is materialized.

The propose value is set to 2097152 KB – this might even be to small. Anyway for this migration it worked fine and I was able to transfer the data without any problem.

So it seems that the materialization of LOB data is not only a performance gain but also the way of handling data within LOBS in influenced.

One thought on “IBM Connections content missing after migration

  1. I had the same issue in a migration. The problem is if you leave out the parameters streamBufferSize and progressiveStreaming for the dbt there is no hint in the logs that you are missing content. But if you use the parameters and the content exceeds the streamBufferSize you get an exception in the dbt logs and you can increase the size.

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