diff --git a/add_missing_indices.sh b/add_missing_indices.sh
index be70042..5ea4353 100755
--- a/add_missing_indices.sh
+++ b/add_missing_indices.sh
@@ -276,6 +276,24 @@ fi
 
 [[ -n "$PHP_ENGINE" ]] || PHP_ENGINE=$DEFAULT_PHP_ENGINE
 
+if [[ "$DATABASE_TYPE" != "postgres" ]] && [[ "$DATABASE_TYPE" != "mysql" ]]; then
+   fatal "Wrong or missing database type (parameter 'DATABASE_TYPE')"
+fi
+
+if [[ -z "$DATABASE_NAME" ]]; then
+   fatal "Missing database name (parameter 'DATABASE_NAME')"
+fi
+
+if [[ "$DATABASE_TYPE" = "mysql" ]] && [[ -z "$MYSQL_CREDENTIALS" ]]; then
+   fatal "No Database Credentials for MySQL given (parameter 'MYSQL_CREDENTIALS')"
+fi
+
+if [[ "$DATABASE_TYPE" = "postgres" ]]; then
+   if [[ -z "$PSQL_USER" ]] || [[ -z "$PSQL_PASS" ]]; then
+      fatal "No Database Credentials for PostgreSQL given (parameters: 'PSQL_USER' 'PSQL_PASS'"
+   fi
+fi
+
 NGINX_IS_ENABLED=false
 APACHE2_IS_ENABLED=false