Jira can be terrible in many ways, but its one saving grace is JQL. (And if a company uses Jira, and its users can't be arsed to learn JQL, then it's a colossal waste of money.)

Is anyone aware of an open source alternative to Jira that supports a similarly versatile query language? Yes, an alternative with an RDBMS backend supporting SQL counts, as long as the application uses a non-brain-breaking data model or provides user-friendly views off its backend tables.

Boosts and comments welcome.