I am looking for a SQL query that will tell me the number of items, size of data, and PST count for a DA export of a case
Lets say, Export1 in CaseID1
Better late answer than no answer. I'm not sure you can get this information (especially the count for PST's) from SQL. Exporting to PST is afterall an action done outside of DA. DA exports the items to an export folder, then instructs Outlook to create PST's with the size you have defined in the export.
As soon as the export is finished, Outlook takes over, which is outside of DA.
The other info (items/size of data) I am not sure about in SQL, but I do believe these are available in one of the reports of DA.