Leggi da file a variabile - Bash Script take2

Usa questo awk con ORS='.*|' :

s=$(awk '$0=="database2"{$0=$0 "*.*";print;next} {$2=$2 ".*"}1' OFS='.' ORS='|' file.txt)
LIST="${s%|}"

echo "$LIST"
database1.table1.*|database1.table4.*|database2*.*|database3.table2.*