2.Warning  – column does not have valid data type.
I encountered this error because of the disabled Logical Table Sources (from warning 39003). The datatype for all the columns belonging to the disabled LTS were set to null.
3.Warning  – There are physical tables mapped in Logical Table Sources that are not used in any column mappings or expressions.
a. Delete the unused logical tables. Delete the aggregations set for that dimension in the content tab of the fact.
b. Create dummy mapping columns from that table.
Metalink note: Warning 39057 [ID 1386095.1]
Cleaning up any unused logical tables pre upgrade, might help from running into this warnings.
4.Warning  – Logical fact table FACTS have an aggregate source that does not join to a Dimension: source at the proper level of detail.
Solution: Make sure there is a physical join between the fact Logical Table Source and dimension’s Logical Table Source. Make sure the aggregation levels are set at the same grain for both dimension and fact on the content tab.
5.Warning  – Logical level does not have any key with Use for Display property on.
‘Use for Display’ option is turned off during the upgrade.
6.Warning  – Logical dimension table has a source that does not join to any fact source.
The Logical levels on the content tab for LTS and Fact table are not set properly.
The join between the LTS and Fact table is missing in the physical layer.
Check for any missing foreign key joins between LTS and Fact table in physical layer.
7.Warning  – Initialization block uses Connection Pool which is used for report queries. This may impact query performance.
8.Warning  – The features in database does not match the defaults. This may cause query problems.
9.Warning  – Logical dimension table has a source with aggregation content set to level ‘Detail’. The same dimension has aggregation content set in fact source to a higher level.