XSLT: Namespace awareness.

This is the short one, I mean it.
If your mapping does not pass the test and you have no  result that you expect to have - check namespaces folks! I'm deadly serious: first check namespaces than start with names, character registers, and syntax. You may save yourself hell lot of the time. 

XSLT. Apples and Oranges.

Believe me or not, I'm not going to compare XSL processors or whining about poor support for XSLT 2.0. Recently I have faced the situation,  where I should merge two property lists and produce combined result. Let's do some shopping and play with the grocery lists. The reasons why I'm writing this post are:

• SOA 11g/12c supports XSLT 2.0 transformations and you can use all the power of it. 
• XSLT Mapper is far behind the processor and may eve lie to you with the error messages. 

The example below is a little trinket, but it may save you hours on developing external services for the data transformation.