Unspecific error for Firebase Data Connect nested SQL inserts

The problem is that execute in Firebase Data Connect only accepts a DML statement(insert, update, delete) Your query is like this:

SELECT id FROM newrecipe;

So this reject with the invalid SQL statement, Data modified CTEs are supported by execute but the final statement has to be inset, update and delete.

WITH ensureuser AS (
  INSERT INTO "User" (id, displayName)
  VALUES ($2, null)
  ON CONFLICT (id) DO NOTHING
)
INSERT INTO Recipe (
  title, authorId, subtitle, description, foodTypes, imageUrl, estimatedMinutes, isTest
)
VALUES ($1,$2,$3,$4,$5,$6,$7,$8);