Introduction

SQLQuack is a Snowflake SQL compiler. It parses Snowflake SQL with its own parser, reports what Snowflake would reject with rustc-style diagnostics, and converts the rest into DuckDB SQL. Every conversion comes from a rule verified against results recorded on Snowflake. Anything no rule covers is refused with a code, the exact span and a reason.

$ sqlquack convert revenue.sql --builtin-policy
error[SQ0004]: a name does not resolve
 --> revenue.sql:2:6
  |
2 | FROM orders
  |      ^^^^^^ relation `ORDERS` has no known columns
  |
  = help: declare the relation and its columns in the schema (`--schema` on the command line)

Once the schema declares ORDERS, the same file converts:

$ sqlquack convert revenue.sql --builtin-policy --schema schema.json
SELECT
    "ORDERS"."CUSTOMER_ID" AS "CUSTOMER_ID",
    CAST(sum("ORDERS"."TOTAL") AS DECIMAL(24,2)) AS "REVENUE"
FROM "ORDERS" AS "ORDERS"
WHERE ("ORDERS"."STATUS" = 'shipped')
GROUP BY "ORDERS"."CUSTOMER_ID"
sqlquack convert: done, converted under the built-in default

What it does

Step	Command	Result
Parse and check	sqlquack check	What Snowflake would reject, as coded diagnostics. No schema needed.
Convert	sqlquack convert	DuckDB SQL for each statement, or the refusals that stop it.
Convert a function	sqlquack function	A SQL project function’s body as a DuckDB macro.
Measure a project	sqlquack census	How much of a body of SQL converts, and what blocks the rest.
Trace rules	sqlquack index	Which rules and building blocks each file’s conversion relies on.

Converted SQL is proven only where both sessions run in UTC: Snowflake’s TIMEZONE and DuckDB’s TimeZone must be 'UTC'. See Policy and sessions.

Quickstart

Build SQLQuack, check a file and convert it.

Playground

Paste Snowflake SQL and see each stage in the browser.

Diagnostics

Every SQ code, what it means and how to fix it.

Python

sqlquack.check and sqlquack.convert from Python.