Replace a word with multiple lines using sed?

Question

I\'m working on a bash-script that has to prepare an E-Mail for being sent to a user.

It aggregates some data, which ends up being multiple lines of stuff. For the e

Answer 1

Echo variable into temporary text file.

Insert text file into mail.tpl and delete data from mail.tpl

echo ${DATA} > temp.txt    
sed -i -e "/_data_/r temp.txt" -e "//d" mail.tpl