But at least it's based on some information available from Oracle.
A new autoupgrade.jar version is available at AutoUpgrade Tool (Doc ID 2485457.1). In this Note, there is also a BUGS_20190715.txt which contains (among others):
AUPG-955 Disable NONCDB validation when upgrading a DB to 20c
AUPG-975 upgrade from 12.1.0.2 to 20 is not supported
Based on that I assume, noncdb will not be officially supported anymore, but maybe it's not supported in the autoupgrade.jar, but manual steps are still allowed & supported - we will se.
Also a direct upgrade from 12.1 to 20 is out of scope of this tool.
But there is more information available.
in the autoupgrade.jar in directory resources/preupgrade/config/ there is a file parameters20.properties. It contains information about deprecated/obsolete/removed parameters.
The changes in comparison to 19 I found:
from deprecated to removed:
unified_audit_sga_queue_size
from deprecated to obsolete:
cluster_database_instances
new parameters and their status:
| PARAMETER | STATUS |
|---|---|
| _arch_sim_mode | removed |
| _gc_async_receive | removed |
| _hcs_disable_sp_jback_opt | removed |
| _autonomous_performance_features_index | removed |
| _cgs_os_level_connection_reqno | deprecated |
| _autonomous_performance_features_stats | removed |
| _px_monitor_load | obsolete |
| _hcs_disable_level_prune_vis_lvs | removed |
| _hcs_disable_level_prune_gby | removed |
| _asm_enable_parity_datafile_creation | removed |
| _part_access_version_by_number | obsolete |
| _tablespace_encryption_default_algorithm | removed |
| _hcs_disable_cell_qry_meas_prune_opt | removed |
| _unified_audit_flush_threshold | removed |
| _optimizer_stats_on_conventional_dml_config | removed |
| _reset_maxcap_history | removed |
| _ldr_io_size2 | obsolete |
| _hang_long_wait_time_threshold | removed |
| _read_mostly_instance | deprecated |
| _cgs_os_level_connection_pthreadno | removed |
| _max_cr_rollbacks | deprecated |
| _hcs_enable_multi_parent_gen | removed |
| _disable_thread_snapshot | removed |
| _hcs_disable_tgt_depths_opt | removed |
| _enable_imc_mira | removed |
| _log_archive_avoid_memcpy | removed |
| _gcs_min_slaves | deprecated |
| _hcs_enable_dynamic_cache | removed |
| _unified_audit_flush_interval | removed |
| _hcs_disable_hord_in_oby_prune | removed |
| _ta_lns_wait_for_arch_log | removed |
| _hcs_disable_jback_opt_for_hord_in_oby | removed |
| _show_mgd_recovery_state | removed |
| _hcs_disable_pushed_preds_in_gen_sql | removed |
| _hcs_disable_cell_qry_tmpls | removed |
| _test_param_5 | deprecated |
| _autonomous_performance_features | removed |
| _session_percent_threshold | removed |
| _ash_compression_enable | deprecated |
| _kebm_max_parallel_intensive_autotasks | removed |
let's see if this will change in next iterations.
The biggest value of such sources (for me) is the reliability. It's not something a vendor wants the customers to know/act on (like a "what changed" document would be); it's the information required by tools, so no political filters are there.
