class_docstr: Calls :meth:`orion.core.io.database.ephemeraldb.EphemeralDocument.select`.
docstr: Select only one field.
docstr_tok: ["Select","only","one","field","."]
code: def test_select_all(self, document):
      """Select only one field."""
      assert document.select({}) == {
          "_id": 1,
          "hello": "there",
          "mighty": "duck",
      }
  
imports: import pytest
  from orion.core.io.database import Database
  from orion.core.io.database.ephemeraldb import EphemeralCollection, EphemeralDB, EphemeralDocument
label_desc: Use image node_id 1 for calling the TestSelect obj's underlying member method code with example usage: obj.test_select_all(document) without return types