Hi All,
I have a trigger on Opportunity with "before Insert and Before Update"   trigger_events.
The code snippet is given below.

for(Opportunity myOpp : trigger.new)
           {
                  if((Trigger.isUpdate)&&(someother condition))
                            //statements_1
                else if(Trigger.isInsert)
                            //statements_2                                            
          }

In most of the cases,Opportunities are inserted/updated in Bulk using Apex DataLoader.    

1. If I use UPSERT opertion using DataLoader, will that cause my records to escape from both the IF statements  ??  
2. Does each record has seperate value for "Trigger.isUpdate" and "Trigger.isInsert" implicit variables??
3. While UPSERTing using DataLoader, if my first set of values causes an UPDATE and the second causes an INSERT, what would be the values of  Trigger.isUpdate and Trigger.isInsert ??

Please help me to clarify these doubts..

Thanks in Advance,
Krishna