Validate Data before Upload

 
To validate the data without uploading it to the interface, place your cursor anywhere on the row(s) containing the data and select the Validate Option of ‘Validate only’, then click 'Upload’ and select ‘Upload Selected'.
 
 
To validate all rows on the sheet at the same time, click the 'Upload’ icon and select 'Upload All' from the ribbon.
 
Refer to section: