When upgrading from 7,11 to 7.12.3 received many warning messages about "AssetSpec" table's maximum row size exceeding 8060 bytes.
ASSETSPEC is a new table created in 7.11 to migrate data from Asset Subtypes to new application architecture.
The table "ASSETSPEC" has been created, but its maximum row size exceeds the allowed maximum of 8060 bytes. INSERT or UPDATE to this table will fail if the resulting row exceeds the size limit.
This is only a warning. If it went over, an error would be written to the upgrade log. Check the upgrade log for errors.