Say I have three Unique(External ID) Fields (Email, Phone, Mobile) But in my file, I do not have values for all three fields for all the rows. But I have atleast value for any one of the field. In this scenario, I need to update the existing records from the file. To achieve this, I need to import for three times. Is there any other better way to import my file without importing the same file for 'n' times?
If you are missing the same values in SF as you are missing in your CSV file, then you can build up a compisite key, say Email-Phone-Mobile.
You'll have to define a calc in Excel that fills in say "null" if the field is blank and do the same in SF in a calc there.
Make sure the order you define the fields in the calc is the same and that they have exactly the same output.
Ie, Excel should show
email@example.com and so should Salesforce.
Then you have a match field that you can use as an external Id.