I would change your Ora_Connection to have an argument for dtDate, and then use this argument in the SQL query.

I would then loop through a range,

so 

Set rngInspect = sheets("Sheet").range("1:1")
do until rngInspect.Cells(1,intOffset)=""
        ora_connection(rngInspect.Cells(1,intOffset).value)
        intOffset=intOffset+1
loop

set rngInspect=Nothing
Something like that. I would also look at keeping the connection open, so have another sub say, Open_DB and Close_DB, so before this Open_DB and at the end Close_DB, saves the opening each time.

Hope this helps

Nathan.