[TYPO3-Solr] Custom Index on tt_content is not refreshe automatically

[Holger]

Ok, I understand that the problem is that we evidently use tt_content in a way that we were not supposed to.Reading your suggestions, I think the right way to solve the problem is to create a new record_monitor. But to be honest I don't know to start. Can help me to start?

But you are also saying that the problem is that we use tt_content for our index. What if I copied the data into a different table and build my index on that? But I guess it would not work, because than I would not have the TCA stuff.

Or would be SQL Triggers also a good idea?
Thanks and sorry for being so slow in understanding your solutions.