Function hasObjects

packages/dofs/src/sync/fetch.ts:47–64

(db: Database, hashes: Uint8Array[])

// rides the primary-key index. Present hashes are returned in input
// order, preserving any duplicates the caller passed.
export function hasObjects(db: Database, hashes: Uint8Array[]): Uint8Array[] {
  if (hashes.length === 0) return [];
  const present = new Set<string>();
  for (let i = 0; i < hashes.length; i += PROBE_BATCH) {
    const window = hashes.slice(i, i + PROBE_BATCH);
    const placeholders = window.map(() => "?").join(", ");
    const rows = db.all<{ hash: Uint8Array }>(
      `SELECT b.hash
         FROM vfs_blobs b
         JOIN vfs_blob_bytes bb ON bb.hash = b.hash
        WHERE b.hash IN (${placeholders})
          AND length(bb.bytes) = b.size`,
      ...window,
    );
    for (const row of rows) present.add(toHex(row.hash));
  }
  return hashes.filter((h) => present.has(toHex(h)));
}