I have changed many client databases on request to use extended datatypes and
experienced no problems at all.
However if you search in oracle support you will find lots of varying errors,
most related to 12.1 only but some more generic.
Here are few:
XDB Invalid after Utlrp during Activation of Extended Datatypes (Doc ID
Database Won't Start After Varchar2(32k) Upgrade (Doc ID 1610329.1)
ORA-00600 [koklismem2: Insufficient Locator Len] on Update of Extended Data
types. (Doc ID 2474129.1)
ORA-01467 In Oracle 12c when max_string_size is Extended Data Types used (Doc
From: oracle-l-bounce@xxxxxxxxxxxxx <oracle-l-bounce@xxxxxxxxxxxxx> On Behalf
Of Jeff Chirco
Sent: Tuesday, October 29, 2019 9:05 AM
To: oracle-l-freelist <oracle-l@xxxxxxxxxxxxx>
Subject: Extended Data types
Has anyone enabled extended data types in 12c to get varchar2(32767) support
for the tables? We are looking to do this but wondering if anyone has
experienced any issues with it cause I know there is no going back once you do.