DB2 12 is classified as an in-memory data base by Gartner. It is not just a simple in-memory data base but a very smart one. In this paper, we explain one of the most innovative in memory optimizations in DB2 12.
XMLModify function is introduced in DB2 10 for z/OS to do sub-document update, without reparsing the whole document. There is a big performance saving if the change is small when comparing to the size of the document.