'GreenSQL is an Open Source database firewall used to protect databases from SQL injection attacks,' says the GreenSQL.net website
, which also says, 'GreenSQL works as a proxy and has built-in support for MySQL and PostgreSQL. The logic is based on evaluation of SQL commands using a risk scoring matrix as well as blocking known db administrative commands (DROP, CREATE, etc).' The company also maintains a commercial version as a separate entity. GreenSQL CTO/CoFounder David Maman gives more details about both the company and open source GreenSQL in this video interview.