No way to exclude properties during an update

I understand that using Dapper.Contrib I can use the Write and Computed attributes to ignore properties during write operations. However, this will ignore the properties on both insert and update. I need a way to ignore properties on updates. My suggestion would be to add 2 attributes... perhaps named Insertable(bool) and Updateable(bool). When a false value is passed to these the framework would exclude that property for the given operation. This is a lightweight, straightforward approach to a very common problem.

Start by reviewing how the Write and Computed attributes are handled for insert and update operations in Dapper.Contrib. Compare those operation paths and determine how the proposed Insertable and Updateable behavior should be defined; done means properties can be excluded from updates without also being excluded from inserts.