diff --git a/Dockerfile b/Dockerfile
index ee9c3d0..1f014f2 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,2 +1,7 @@
-FROM postgres:9.6
+FROM library/postgres:9.6-alpine
+
 COPY create-multiple-postgresql-databases.sh /docker-entrypoint-initdb.d/
+
+RUN chmod +x /docker-entrypoint-initdb.d/create-multiple-postgresql-databases.sh
+
+EXPOSE 5432
diff --git a/create-multiple-postgresql-databases.sh b/create-multiple-postgresql-databases.sh
index aa665fa..41f0226 100755
--- a/create-multiple-postgresql-databases.sh
+++ b/create-multiple-postgresql-databases.sh
@@ -4,18 +4,32 @@ set -e
 set -u
 
 function create_user_and_database() {
-	local database=$1
+	local database=$(echo $1 | tr ',' ' ' | awk  '{print $1}')
+	local owner=$(echo $1 | tr ',' ' ' | awk  '{print $2}')
 	echo "  Creating user and database '$database'"
 	psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" <<-EOSQL
-	    CREATE USER $database;
-	    CREATE DATABASE $database;
-	    GRANT ALL PRIVILEGES ON DATABASE $database TO $database;
-EOSQL
+		DO
+		\$do\$
+	    BEGIN
+			IF EXISTS (
+				SELECT * FROM pg_catalog.pg_user
+				WHERE pg_user.usename = '$owner'
+			) THEN
+				RAISE NOTICE 'Role $owner already exists, skipping creation';
+			ELSE
+				CREATE USER "$owner" LOGIN PASSWORD '$POSTGRES_PASSWORD';
+			END IF;
+		END
+		\$do\$;
+	    CREATE DATABASE "$database";
+	    GRANT ALL ON DATABASE "$database" TO "$owner";
+		ALTER DATABASE "$database" OWNER TO "$owner";
+	EOSQL
 }
 
 if [ -n "$POSTGRES_MULTIPLE_DATABASES" ]; then
 	echo "Multiple database creation requested: $POSTGRES_MULTIPLE_DATABASES"
-	for db in $(echo $POSTGRES_MULTIPLE_DATABASES | tr ',' ' '); do
+	for db in $(echo $POSTGRES_MULTIPLE_DATABASES | tr ':' ' '); do
 		create_user_and_database $db
 	done
 	echo "Multiple databases created"