Cloud-data specialist Snowflake, which reached a $70 billion valuation with its public debut in September, has made its first corporate venture capital deal. Snowflake Ventures has joined a $50 million add-on deal for DataRobot, a Boston-based data-science startup. Also participating in the funding were Salesforce Ventures and Hewlett Packard Enterprise, bringing the Series F round to a total of $320 million. The round was led by Altimeter Capital in November. Snowflake Ventures, which launched last month, targets investments of between $1 million and $5 million in data-related companies.