XDB Clean Up in Oracle Database 11.2-12.2 will apply to Oracle Database 11.2.0.x only as XDB became a mandatory component since Oracle Database 12.1.0.1. You can’t have an Oracle 12c database without XDB. Therefore the following blog post won’t explain how to clean up XDB from an Oracle 12c database. It explains only briefly the case before Oracle Database 12c.
XDB Clean Up in Oracle Database 11.2-12.2
Oracle XML DB provides full support for all of the key XML standards, including XML, Namespaces, DOM, XQuery, SQL/XML and XSLT. By providing full support for XML standards, Oracle XML DB …
Oracle Label Security (OLS) clean up in Oracle Database 11.2-19c is almost as simple and straight forward as removing OWM or APEX. You can do it online without downtime. But in older releases a relink operation did cause downtime. Oracle Label Security is an 
Oracle Label Security is dependent on Oracle Database Vault (DV). In case DV is present you must remove it first if you plan to remove Oracle Label Security.
