Some examples of things that will cause a non-optimised load are:
- Adding new fields to the table - Deriving new values from a field in the QVD - Retrieving a field twice - Most WHERE conditions - Joining to an existing in memory table - Loading data into a mapping table
In contrast the things you are allowed to do are:
- Rename fields - Omit fields - Do a simple one field WHERE EXISTS on a field returned in the record set
