marketing-cloud-campaign-personalisation.ampscript

%%[
var @subscriberRows 
set @subscriberRows = RetrieveSalesforceObjects( "Contact", "FirstName, Id", "Id", "=", _subscriberKey) 
if RowCount(@subscriberRows) == 1 then /* there should only be one row */ 
    var @subscriberRow, @FirstName, @Id 
    set @subscriberRow = Row(@subscriberRows, 1) 
    set @FirstName = Field(@subscriberRow, "FirstName")
    set @Id = Field(@subscriberRow, "Id")
endif 

if length(@FirstName) <= 0 then 
    set @FirstName = 'Friend'
endif
]%%

%%=v(@FirstName)=%%