Hi Henrik,
I am unconvinced that the JDBC Store node is not the better option, but I'll answer. I have not tested to see if this approach to creating that SQL insert statement is faster.
I often run across the need to build a single string value using a concatenated lest of values from multiple records like you are describing, I've started structuring it like this:
In ConfigureFields I define an empty Python List object:
In the ProcessRecords property I append() all the values to this list, and then at the end I have Python create the string from the values in the list. Python has a very nice syntax for doing this using the join() method.

Back to your question, I am wondering if there is some sort of limit on the number of entries that are reasonable to put together in a list. Maybe breaking it up into 1000 record insert statements would be better for the database to manage.
And the reason I wonder if the JDBC Store node would not be better is I wonder if you've tried to use the Optional properties that can make it run faster. Maybe the Commit Frequency needs to be increased to 10,000 or 100,000.
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Ernest Jones
Precisely Software Inc.
PEARL RIVER NY
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