sqlite virtual table silently returns empty rows for unavailable join parameters #66214

Version

main

Platform

All

Subsystem

sqlite

What steps will reproduce the bug?

import { DatabaseSync } from 'node:sqlite';

const db = new DatabaseSync(':memory:');

db.createModule('m', {
  columns: [
    { name: 'value', type: 'INTEGER' },
    { name: 'a', type: 'INTEGER', hidden: true },
  ],
  *rows(a) { if (a !== null) yield [a]; },
});

db.exec('CREATE TABLE t (a INTEGER)');
db.exec('INSERT INTO t VALUES (1), (2), (3)');

console.log(db.prepare('SELECT DISTINCT * FROM m(t.a) JOIN t ON t.a = m.a').all());

How often does it reproduce? Is there a required condition?

Always

What is the expected behavior? Why is that the expected behavior?

Per SQLite's Enforcing Required Parameters On Table-Valued Functions, xBestIndex() must return SQLITE_CONSTRAINT when a parameter has an EQ constraint whose usable flag is false, so the planner picks an ordering where the parameter is available. Cost estimates alone cannot enforce parameter dependencies.

What do you see instead?

rows() is called with null and the query returns []. xBestIndex() skips constraints with usable == false, accepts the unconstrained plan, and xFilter() passes Null(isolate).

Additional information

No response