MemSQL is a real-time database that allows users to simultaneously ingest, serve, and analyze streaming data and transactions. It is an in-memory distributed relational database that supports SQL, key-value, documents, and geospatial queries. MemSQL provides real-time analytics capabilities through Streamliner, which allows one-click deployment of Apache Spark for real-time data pipelines and analytics without batch processing. It is available in free community and paid enterprise editions with support and additional features.