Sorry to start with some kind of criticism when dealing with brand-new v17... - but the really impressive whole bunch of new features (*) makes it difficult to find out what behaviour changes are relevant for existing applications.
AFAIK, all older versions had separate "Behavior Changes" and "Deprecated and removed features" pages (although it might sometimes be debatable if some feature is new or changed...), and we are too used to recommend "read all those pages when upgrading from an older version".
In contrast, the v17 "SQL Anywhere - Changes and Upgrading" book does not contain those different topics, and enhancements and changes seem to be listed somewhat mixed, which makes it harder to tell one from another.
Why is that?
(*) - That impression is partially due to the lack of published beta versions, isn't it?
Each of the "What's New" and "Changes to..." topics contain a section titled "Behavior changes and deprecated or removed features". Here is the link to the "Changes to SQL statements, function, procedures, and data types" topic. Scroll down about half way to see the section.
Just to add:
As of the v17.0.4 release, the doc set has been updated, according to Jack's comment (*), and now the "SQL Anywhere Server" topic has
(The other main topics like MobiLink and UltraLite don't have such sub-topics but that's ok with me, as their lists are way shorter.)
Thanks for listening:)
(*) - And that may explain why I could not find my older DCX comments:)