excel export - few options

Hi all,

i have a simple php script which pulls data from mysql db and displays it. i
would like to add the option to export the displayed table to an excel
spreadsheet with the click of a button.
i've done some googling and it seems the best way is to call onclick a
seperate php file with the excel header which will then prompt user to save
file.
since am n00b, i appreciate its a bit longwinded so my question is: is there
a better and efficient way since the data has already been retrieved; why go
again an retrieve it ?

all suggestions are appreciated