Grant SELECT access to a user for all tables in a PostgreSql DB

grant.sh

#!/bin/bash
echo '---------------------------------------------------------------'
echo 'Grant SELECT access to a user for all tables in a PostgreSql DB'
echo '[USAGE]:    ./scriptname username dbname'
echo '---------------------------------------------------------------'
for table in `echo "SELECT schemaname || '.' || relname FROM pg_stat_all_tables;" | psql $2 | grep -v "pg_" | grep "^ " | grep -v "\?column\?"`;
do
    echo "GRANT SELECT ON TABLE $table TO $1;"
    echo "GRANT SELECT ON TABLE $table TO $1;" | psql $2
done