diff --git a/participants/__init__.py b/participants/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/participants/query_db.py b/participants/query_db.py
new file mode 100644
index 0000000..087d185
--- /dev/null
+++ b/participants/query_db.py
@@ -0,0 +1,27 @@
+import datetime
+from collections.abc import Collection
+
+import pandas as pd
+from sqlalchemy import and_
+
+from config.models import Participant
+from setup import db_engine, session
+
+
+def get_usernames(
+    tester: bool = False,
+    active: bool = False,
+    collection_start: datetime.date = datetime.date.fromisoformat("2020-01-01"),
+    last_upload: datetime.date = datetime.date.today(),
+) -> Collection:
+    query_participant_usernames = session.query(Participant.username).filter(
+        and_(
+            Participant.tester == tester,
+            Participant.active == active,
+            Participant.collection_start_utc >= collection_start,
+            Participant.last_upload_utc < last_upload,
+        )
+    )
+    with db_engine.connect() as connection:
+        df_participants = pd.read_sql(query_participant_usernames.statement, connection)
+    return df_participants
diff --git a/test/test_participants.py b/test/test_participants.py
new file mode 100644
index 0000000..e449d70
--- /dev/null
+++ b/test/test_participants.py
@@ -0,0 +1,10 @@
+import unittest
+
+from participants.query_db import get_usernames
+
+
+class CallsFeatures(unittest.TestCase):
+    def test_get_usernames(self):
+        usernames_from_db = get_usernames()
+        print(usernames_from_db)
+        self.assertIsNotNone(usernames_from_db)