FlyQL

A lightweight query language that transpiles into injection-proof SQL across ClickHouse, PostgreSQL, and StarRocks — with implementations in Go, Python, and JavaScript.

What is FlyQL?

FlyQL is a simple, human-readable query language designed for filtering data. Write a query like status>=400 and host=prod*, and FlyQL transpiles it into parameterized SQL for your database — or evaluates it in-memory against data records.

status>=400 and host=prod* and not debug

This query works identically whether your backend is ClickHouse, PostgreSQL, StarRocks, or an in-memory dataset.

Key Features

• Injection-Proof by Design — The grammar cannot express subqueries, JOINs, UNIONs, or DDL. Security is structural, not defensive. All generated SQL uses parameterized values.
• Multi-Dialect SQL — One query language, dialect-specific output. Generates correct SQL for ClickHouse, PostgreSQL, and StarRocks with proper type handling (JSON paths, Map access, Array handling).
• Multi-Language — Full implementations in Go, Python, and JavaScript. Parse on the frontend, validate on the backend, generate SQL anywhere — same query, same results.
• Zero Dependencies — Hand-written state-machine parser with no external dependencies in any language. Trivial to integrate, nothing to conflict with.

Quick Example

service!=api and (status>=400 or level=error) and message~"timeout.*"

Component	Meaning
service!=api	service field is not “api”
status>=400	status is 400 or greater
level=error	level field equals “error”
message~"timeout.*"	message matches regex pattern
and, or	boolean logic with precedence
( )	explicit grouping

Supported Languages

Language	Parser	SQL Generators	In-Memory Matcher
Go	Yes	ClickHouse, PostgreSQL, StarRocks	Yes
Python	Yes	ClickHouse, PostgreSQL, StarRocks	Yes
JavaScript	Yes	ClickHouse, PostgreSQL, StarRocks	Yes