just a little bug report. I used the column rename node, renaming a Integer Column to Long Column. Sadly the result was not a Long-Column-Type, but a bunch implemented Interfaces. See the screenshots.
PS> I did not find a bug tracker or something similar to post this bug.
As the name of the node already indicates, it's not meant to to convert data types but for renaming. The fact that you can also "cast" is historical and confused a lot of people but we cannot remove this functionality without breaking existing workflows. Usually there is no reason to convert an integer column to a long column because all nodes should be able to use an integer for a long value. Which node strictly requires a long column?
I am splitting a String into several bits, one of them is a DB id, which gets converted to type Integer. Later on, I use the joiner node with that ID, having the other table an ID as Long.
I know, that I can cast types with a simple java node.
Use a String Manipulation Node to remove the commas in the number. Then use a String to Number node. Select Type as Number (Long).