-[[ -z "$SQL_SRC_DIR" ]] && { echo "Error: SQL_SRC_DIR must be provided as an environment variable"; exit 1; }
-[[ -z "$DB_USER" ]] && { echo "Error: DB_USER must be provided as an environment variable"; exit 1; }
-[[ -z "$DB_PASS" ]] && { echo "Error: DB_PASS must be provided as an environment variable"; exit 1; }
-[[ -z "$DB_HOST" ]] && { echo "Error: DB_HOST must be provided as an environment variable"; exit 1; }
+[ -z "$SQL_SRC_DIR" ] && { echo "Error: SQL_SRC_DIR must be provided as an environment variable"; exit 1; }
+[ -z "$DB_USER" ] && { echo "Error: DB_USER must be provided as an environment variable"; exit 1; }
+[ -z "$DB_PASS" ] && { echo "Error: DB_PASS must be provided as an environment variable"; exit 1; }
+[ -z "$DB_HOST" ] && { echo "Error: DB_HOST must be provided as an environment variable"; exit 1; }