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diff --git a/ca_core/__init__.py b/ca_core/__init__.py
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diff --git a/ca_core/__pycache__/property.cpython-313.pyc b/ca_core/__pycache__/property.cpython-313.pyc
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diff --git a/ca_core/entity.py b/ca_core/entity.py
new file mode 100644
index 0000000..0b26849
--- /dev/null
+++ b/ca_core/entity.py
@@ -0,0 +1,170 @@
+import random
+import string
+
+# ------------------------
+# Helper for ownership checks (Option 2)
+# ------------------------
+def _verify_ownership(cursor, entity_id, requesting_creator_id):
+    cursor.execute("SELECT id, creator FROM entity WHERE id=%s", (entity_id,))
+    row = cursor.fetchone()
+    if not row:
+        raise ValueError("Entity not found")
+    owner_id = row["creator"]
+    entity_id_db = row["id"]
+
+    if owner_id is None:
+        # Entity is a creator → allow only self
+        if requesting_creator_id != entity_id_db:
+            raise ValueError("Creator ID does not match entity owner")
+    else:
+        # Entity is a person/group → allow original creator
+        if requesting_creator_id != owner_id:
+            raise ValueError("Creator ID does not match entity owner")
+
+
+# ------------------------
+# Insertions
+# ------------------------
+def insert_creator(cursor, name, public_key):
+    cursor.execute(
+        """
+        INSERT INTO entity (name, group_p, public_key, creator)
+        VALUES (%s, FALSE, %s, NULL)
+        RETURNING id
+        """,
+        (name, public_key)
+    )
+    return cursor.fetchone()["id"]
+
+
+def enroll_person(cursor, name, public_key, creator_id):
+    cursor.execute("SELECT creator FROM entity WHERE id=%s", (creator_id,))
+    row = cursor.fetchone()
+    if not row or row["creator"] is not None:
+        raise ValueError("Provided creator_id does not correspond to a creator")
+    cursor.execute(
+        """
+        INSERT INTO entity (name, group_p, public_key, creator)
+        VALUES (%s, FALSE, %s, %s)
+        RETURNING id
+        """,
+        (name, public_key, creator_id)
+    )
+    return cursor.fetchone()["id"]
+
+
+def create_group(cursor, name, public_key, creator_id):
+    cursor.execute("SELECT creator FROM entity WHERE id=%s", (creator_id,))
+    row = cursor.fetchone()
+    if not row or row["creator"] is not None:
+        raise ValueError("Provided creator_id does not correspond to a creator")
+    cursor.execute(
+        """
+        INSERT INTO entity (name, group_p, public_key, creator)
+        VALUES (%s, TRUE, %s, %s)
+        RETURNING id
+        """,
+        (name, public_key, creator_id)
+    )
+    return cursor.fetchone()["id"]
+
+
+def create_alias(cursor, person_id):
+    cursor.execute("SELECT id, group_p, public_key FROM entity WHERE id=%s", (person_id,))
+    row = cursor.fetchone()
+    if not row:
+        raise ValueError("Person not found")
+    if row["group_p"]:
+        raise ValueError("Groups cannot create aliases")
+    random_name = ''.join(random.choices(string.ascii_letters + string.digits, k=8))
+    cursor.execute(
+        """
+        INSERT INTO entity (name, group_p, public_key, creator)
+        VALUES (%s, FALSE, %s, %s)
+        RETURNING id
+        """,
+        (random_name, row["public_key"], person_id)
+    )
+    return cursor.fetchone()["id"]
+
+
+# ------------------------
+# Deletion
+# ------------------------
+def delete_person(cursor, person_id, requesting_creator_id):
+    _verify_ownership(cursor, person_id, requesting_creator_id)
+    cursor.execute("DELETE FROM entity WHERE id=%s AND group_p=FALSE", (person_id,))
+    if cursor.rowcount == 0:
+        raise ValueError("Person not found or already deleted")
+
+
+def delete_group(cursor, group_id, requesting_creator_id):
+    _verify_ownership(cursor, group_id, requesting_creator_id)
+    cursor.execute("DELETE FROM entity WHERE id=%s AND group_p=TRUE", (group_id,))
+    if cursor.rowcount == 0:
+        raise ValueError("Group not found or already deleted")
+
+
+def delete_creator(cursor, creator_id, requesting_creator_id):
+    _verify_ownership(cursor, creator_id, requesting_creator_id)
+    # check if creator has created other entities
+    cursor.execute("SELECT COUNT(*) as cnt FROM entity WHERE creator=%s", (creator_id,))
+    if cursor.fetchone()["cnt"] > 0:
+        raise ValueError("Creator cannot be deleted because it has created other entities")
+    cursor.execute("DELETE FROM entity WHERE id=%s AND creator IS NULL", (creator_id,))
+    if cursor.rowcount == 0:
+        raise ValueError("Creator not found or already deleted")
+
+
+# ------------------------
+# Getters
+# ------------------------
+def get_entity(cursor, entity_id):
+    cursor.execute("SELECT * FROM entity WHERE id=%s", (entity_id,))
+    row = cursor.fetchone()
+    if not row:
+        raise ValueError("Entity not found")
+    return row
+
+
+def get_entity_id(cursor, name):
+    cursor.execute("SELECT id FROM entity WHERE name=%s", (name,))
+    row = cursor.fetchone()
+    if not row:
+        raise ValueError("Entity not found")
+    return row["id"]
+
+
+def get_entity_public_key(cursor, entity_id):
+    cursor.execute("SELECT public_key FROM entity WHERE id=%s", (entity_id,))
+    row = cursor.fetchone()
+    if not row:
+        raise ValueError("Entity not found")
+    return row["public_key"]
+
+
+def get_entity_name(cursor, entity_id):
+    cursor.execute("SELECT name FROM entity WHERE id=%s", (entity_id,))
+    row = cursor.fetchone()
+    if not row:
+        raise ValueError("Entity not found")
+    return row["name"]
+
+
+# ------------------------
+# Setters
+# ------------------------
+def set_entity_name(cursor, entity_id, new_name, requesting_creator_id):
+    _verify_ownership(cursor, entity_id, requesting_creator_id)
+    cursor.execute("UPDATE entity SET name=%s WHERE id=%s", (new_name, entity_id))
+
+
+def set_entity_public_key(cursor, entity_id, public_key, requesting_creator_id):
+    _verify_ownership(cursor, entity_id, requesting_creator_id)
+    cursor.execute("UPDATE entity SET public_key=%s WHERE id=%s", (public_key, entity_id))
+
+
+def set_entity_keys(cursor, entity_id, public_key, requesting_creator_id):
+    # only public_key for current schema
+    set_entity_public_key(cursor, entity_id, public_key, requesting_creator_id)
+
diff --git a/ca_core/group_member.py b/ca_core/group_member.py
new file mode 100644
index 0000000..36216db
--- /dev/null
+++ b/ca_core/group_member.py
@@ -0,0 +1,28 @@
+# ca_core/group_member.py
+
+def add_group_member(cursor, group_id: int, person_id: int, role: str):
+    cursor.execute(
+        "INSERT INTO group_member (group_id, person_id, role) VALUES (%s, %s, %s)",
+        (group_id, person_id, role)
+    )
+
+def remove_group_member(cursor, group_id: int, person_id: int):
+    cursor.execute(
+        "DELETE FROM group_member WHERE group_id = %s AND person_id = %s",
+        (group_id, person_id)
+    )
+
+def get_groups_for_person(cursor, person_id: int):
+    cursor.execute(
+        "SELECT group_id, role FROM group_member WHERE person_id = %s",
+        (person_id,)
+    )
+    return cursor.fetchall()
+
+def get_members_of_group(cursor, group_id: int):
+    cursor.execute(
+        "SELECT person_id, role FROM group_member WHERE group_id = %s",
+        (group_id,)
+    )
+    return cursor.fetchall()
+
diff --git a/ca_core/metadata.py b/ca_core/metadata.py
new file mode 100644
index 0000000..dc1cdb3
--- /dev/null
+++ b/ca_core/metadata.py
@@ -0,0 +1,35 @@
+def get_name(cursor):
+    cursor.execute("SELECT name FROM metadata LIMIT 1")
+    row = cursor.fetchone()
+    return row['name'] if row else None
+
+def set_name(cursor, value):
+    cursor.execute("UPDATE metadata SET name = %s", (value,))
+
+def get_comment(cursor):
+    cursor.execute("SELECT comment FROM metadata LIMIT 1")
+    row = cursor.fetchone()
+    return row['comment'] if row else None
+
+def set_comment(cursor, value):
+    cursor.execute("UPDATE metadata SET comment = %s", (value,))
+
+def get_public_key(cursor):
+    cursor.execute("SELECT public_key FROM metadata LIMIT 1")
+    row = cursor.fetchone()
+    return row['public_key'] if row else None
+
+def get_private_key(cursor):
+    cursor.execute("SELECT private_key FROM metadata LIMIT 1")
+    row = cursor.fetchone()
+    return row['private_key'] if row else None
+
+def set_keys(cursor, public_key, private_key):
+    """
+    Sets both public and private keys together
+    """
+    cursor.execute("""
+        UPDATE metadata
+        SET public_key = %s, private_key = %s
+    """, (public_key, private_key))
+
diff --git a/ca_core/property.py b/ca_core/property.py
new file mode 100644
index 0000000..ff30d4d
--- /dev/null
+++ b/ca_core/property.py
@@ -0,0 +1,33 @@
+def set_property(cursor, entity_id: int, property_name: str):
+    """
+    Adds a property for the entity. If it already exists, does nothing.
+    """
+    cursor.execute("""
+        INSERT INTO property (id, property_name)
+        VALUES (%s, %s)
+        ON CONFLICT (id, property_name) DO NOTHING
+    """, (entity_id, property_name))
+
+def delete_property(cursor, entity_id, property_name):
+    """
+    Remove a property from an entity.
+    Raises ValueError if the property does not exist.
+    """
+    cursor.execute(
+        "DELETE FROM property WHERE id=%s AND property_name=%s",
+        (entity_id, property_name)
+    )
+    if cursor.rowcount == 0:
+        raise ValueError("Property not found")
+
+def get_properties(cursor, entity_id: int):
+    """
+    Returns a list of property names for the given entity.
+    """
+    cursor.execute("""
+        SELECT property_name
+        FROM property
+        WHERE id = %s
+    """, (entity_id,))
+    return [row['property_name'] for row in cursor.fetchall()]
+
diff --git a/create_tables.sql b/create_tables.sql
index 6d6cf5d..581ccf4 100644
--- a/create_tables.sql
+++ b/create_tables.sql
@@ -1,8 +1,20 @@
-drop table entity;
+drop table metadata;
+
+create table metadata(
+   name varchar(50),
+   comment varchar(200),
+   private_key varchar(500),
+   public_key varchar(500)
+);
+
+insert into metadata default vALUES;
+
+drop table entity cascade;
 
 create table entity(
    id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    creation_ts TIMESTAMPTZ NOT NULL DEFAULT now(),
+   creator INT REFERENCES entity(id),
    name varchar(100) NOT NULL,
    group_p BOOLEAN NOT NULL,
    geo_offset BIGINT,
@@ -16,8 +28,8 @@ create table entity(
 drop table group_member;
 
 create table group_member(
-   group_id INT,
-   person_id INT,
+   group_id INT NOT NULL REFERENCES entity(id) ON DELETE CASCADE,
+   person_id INT NOT NULL REFERENCES entity(id)  ON DELETE CASCADE,
    role VARCHAR(10),
    PRIMARY KEY (group_id,person_id)
 );
@@ -25,6 +37,7 @@ create table group_member(
 drop table property;
 
 create table property(
-   id INT NOT NULL,
-   property_name VARCHAR(100)
+   id INT NOT NULL REFERENCES entity(id) ON DELETE CASCADE,
+   property_name VARCHAR(100),
+   PRIMARY KEY (id, property_name)
 );
diff --git a/tests/.create_testdata.sql.swp b/tests/.create_testdata.sql.swp
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diff --git a/tests/test_entity.py b/tests/test_entity.py
new file mode 100644
index 0000000..786a88e
--- /dev/null
+++ b/tests/test_entity.py
@@ -0,0 +1,97 @@
+import unittest
+import psycopg
+from psycopg.rows import dict_row
+from ca_core import entity
+
+class TestEntity(unittest.TestCase):
+
+    def setUp(self):
+        self.conn = psycopg.connect("dbname=ca")
+        self.conn.autocommit = False
+        self.cur = self.conn.cursor(row_factory=dict_row)
+
+        # Clean table
+        self.cur.execute("TRUNCATE TABLE entity CASCADE;")
+
+        # Insert creator
+        self.creator_id = entity.insert_creator(self.cur, "Alice", "pubkeyA")
+
+        # Insert person
+        self.person_id = entity.enroll_person(self.cur, "Bob", "pubkeyB", self.creator_id)
+
+        # Insert group
+        self.group_id = entity.create_group(self.cur, "Admins", "gpub", self.creator_id)
+
+    def tearDown(self):
+        self.conn.rollback()
+        self.cur.close()
+        self.conn.close()
+
+    # -------------------------
+    # Lookup
+    # -------------------------
+    def test_get_entity_by_id(self):
+        ent = entity.get_entity(self.cur, self.person_id)
+        self.assertEqual(ent["id"], self.person_id)
+        self.assertFalse(ent["group_p"])
+        self.assertEqual(ent["creator"], self.creator_id)
+        self.assertEqual(ent["name"], "Bob")
+
+    def test_get_entity_id_by_name(self):
+        eid = entity.get_entity_id(self.cur, "Bob")
+        self.assertEqual(eid, self.person_id)
+
+    # -------------------------
+    # Setters / Getters
+    # -------------------------
+    def test_set_entity_name_with_creator(self):
+        entity.set_entity_name(self.cur, self.person_id, "Robert", self.creator_id)
+        self.assertEqual(entity.get_entity_name(self.cur, self.person_id), "Robert")
+
+    def test_set_entity_name_wrong_creator(self):
+        with self.assertRaises(ValueError):
+            entity.set_entity_name(self.cur, self.person_id, "Robert", 999999)
+
+    def test_set_entity_keys(self):
+        entity.set_entity_keys(self.cur, self.person_id, "new_pub", self.creator_id)
+        self.assertEqual(entity.get_entity_public_key(self.cur, self.person_id), "new_pub")
+
+    # -------------------------
+    # Creator self-update
+    # -------------------------
+    def test_set_entity_name_creator_self(self):
+        entity.set_entity_name(self.cur, self.creator_id, "Alicia", self.creator_id)
+        self.assertEqual(entity.get_entity_name(self.cur, self.creator_id), "Alicia")
+
+    # -------------------------
+    # Aliases
+    # -------------------------
+    def test_create_alias(self):
+        alias_id = entity.create_alias(self.cur, self.person_id)
+        alias = entity.get_entity(self.cur, alias_id)
+        self.assertFalse(alias["group_p"])
+        self.assertEqual(alias["creator"], self.person_id)
+        self.assertNotEqual(alias["name"], "Bob")
+        self.assertEqual(alias["public_key"], "pubkeyB")
+
+    # -------------------------
+    # Deletion
+    # -------------------------
+    def test_delete_person(self):
+        entity.delete_person(self.cur, self.person_id, self.creator_id)
+        with self.assertRaises(ValueError):
+            entity.get_entity(self.cur, self.person_id)
+
+    def test_delete_group(self):
+        entity.delete_group(self.cur, self.group_id, self.creator_id)
+        with self.assertRaises(ValueError):
+            entity.get_entity(self.cur, self.group_id)
+
+    def test_delete_creator_with_dependents(self):
+        with self.assertRaises(ValueError):
+            entity.delete_creator(self.cur, self.creator_id, self.creator_id)
+
+
+if __name__ == "__main__":
+    unittest.main()
+
diff --git a/tests/test_group.py b/tests/test_group.py
new file mode 100644
index 0000000..b20f6e6
--- /dev/null
+++ b/tests/test_group.py
@@ -0,0 +1,89 @@
+import unittest
+import psycopg
+from psycopg.rows import dict_row
+from ca_core import entity, group_member  # <-- your code package
+
+class TestGroupMember(unittest.TestCase):
+    """Unit tests for group_member functionality including cascade deletions."""
+
+    def setUp(self):
+        self.conn = psycopg.connect("dbname=ca")
+        self.conn.autocommit = False
+        self.cur = self.conn.cursor(row_factory=dict_row)
+
+        # Create a creator
+        self.creator_id = entity.insert_creator(self.cur, "Alice", "pubkeyA")
+
+        # Create two persons
+        self.person1_id = entity.enroll_person(self.cur, "Bob", "pubkeyB", self.creator_id)
+        self.person2_id = entity.enroll_person(self.cur, "Charlie", "pubkeyC", self.creator_id)
+
+        # Create a group
+        self.group_id = entity.create_group(self.cur, "Admins", "gpub", self.creator_id)
+
+    def tearDown(self):
+        self.conn.rollback()
+        self.cur.close()
+        self.conn.close()
+
+    # -------------------------
+    # Add / remove members
+    # -------------------------
+
+    def test_add_member(self):
+        group_member.add_group_member(self.cur, self.group_id, self.person1_id, "member")
+        members = group_member.get_members_of_group(self.cur, self.group_id)
+
+        self.assertEqual(len(members), 1)
+        self.assertEqual(members[0]["person_id"], self.person1_id)
+        self.assertEqual(members[0]["role"], "member")
+
+    def test_remove_member(self):
+        group_member.add_group_member(self.cur, self.group_id, self.person1_id, "member")
+        group_member.remove_group_member(self.cur, self.group_id, self.person1_id)
+        members = group_member.get_members_of_group(self.cur, self.group_id)
+        self.assertEqual(len(members), 0)
+
+    def test_get_groups_for_person(self):
+        group_member.add_group_member(self.cur, self.group_id, self.person1_id, "admin")
+        group_member.add_group_member(self.cur, self.group_id, self.person2_id, "member")
+
+        groups = group_member.get_groups_for_person(self.cur, self.person2_id)
+        self.assertEqual(len(groups), 1)
+        self.assertEqual(groups[0]["group_id"], self.group_id)
+        self.assertEqual(groups[0]["role"], "member")
+
+    # -------------------------
+    # Cascade deletion tests
+    # -------------------------
+
+    def test_cascade_delete_person(self):
+        group_member.add_group_member(self.cur, self.group_id, self.person1_id, "admin")
+        group_member.add_group_member(self.cur, self.group_id, self.person2_id, "member")
+
+        # Delete person1
+        entity.delete_person(self.cur, self.person1_id, self.creator_id)
+
+        # Membership should be gone for person1
+        members = group_member.get_members_of_group(self.cur, self.group_id)
+        self.assertEqual(len(members), 1)
+        self.assertEqual(members[0]["person_id"], self.person2_id)
+
+    def test_cascade_delete_group(self):
+        group_member.add_group_member(self.cur, self.group_id, self.person1_id, "admin")
+        group_member.add_group_member(self.cur, self.group_id, self.person2_id, "member")
+
+        # Delete the group
+        entity.delete_group(self.cur, self.group_id, self.creator_id)
+
+        # Persons should have no group membership
+        groups_person1 = group_member.get_groups_for_person(self.cur, self.person1_id)
+        groups_person2 = group_member.get_groups_for_person(self.cur, self.person2_id)
+
+        self.assertEqual(len(groups_person1), 0)
+        self.assertEqual(len(groups_person2), 0)
+
+
+if __name__ == "__main__":
+    unittest.main()
+
diff --git a/tests/test_metadata.py b/tests/test_metadata.py
new file mode 100755
index 0000000..2604121
--- /dev/null
+++ b/tests/test_metadata.py
@@ -0,0 +1,76 @@
+import unittest
+import sys
+from pathlib import Path
+import psycopg
+
+# Add the code directory to Python path
+code_path = Path(__file__).parent.parent / "ca_core"
+sys.path.insert(0, str(code_path))
+
+import metadata  # your metadata.py module
+
+DBNAME = "ca"
+
+class TestMetadataFunctions(unittest.TestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        # Connect to the database
+        cls.conn = psycopg.connect(f"dbname={DBNAME}")
+        cls.cur = cls.conn.cursor(row_factory=psycopg.rows.dict_row)
+
+        # Ensure table exists and has exactly one row
+        cls.cur.execute("""
+            CREATE TABLE IF NOT EXISTS metadata (
+                name VARCHAR(50),
+                comment VARCHAR(200),
+                private_key VARCHAR(500),
+                public_key VARCHAR(500)
+            )
+        """)
+        cls.cur.execute("SELECT COUNT(*) AS cnt FROM metadata")
+        row = cls.cur.fetchone()
+        if row['cnt'] == 0:
+            cls.cur.execute("INSERT INTO metadata DEFAULT VALUES")
+        cls.conn.commit()
+
+    @classmethod
+    def tearDownClass(cls):
+        cls.cur.close()
+        cls.conn.close()
+
+    def setUp(self):
+        # Begin transaction for each test
+        self.conn.rollback()
+        self.conn.autocommit = False
+
+    def tearDown(self):
+        # Rollback after each test
+        self.conn.rollback()
+
+    # --- Test name field ---
+    def test_set_and_get_name(self):
+        metadata.set_name(self.cur, "AppName")
+        self.assertEqual(metadata.get_name(self.cur), "AppName")
+
+    # --- Test comment field ---
+    def test_set_and_get_comment(self):
+        metadata.set_comment(self.cur, "Test comment")
+        self.assertEqual(metadata.get_comment(self.cur), "Test comment")
+
+    # --- Test keys ---
+    def test_set_and_get_keys(self):
+        metadata.set_keys(self.cur, "pubkey123", "privkey456")
+        self.assertEqual(metadata.get_public_key(self.cur), "pubkey123")
+        self.assertEqual(metadata.get_private_key(self.cur), "privkey456")
+
+    # --- Test keys overwrite ---
+    def test_keys_overwrite(self):
+        metadata.set_keys(self.cur, "pub1", "priv1")
+        metadata.set_keys(self.cur, "pub2", "priv2")
+        self.assertEqual(metadata.get_public_key(self.cur), "pub2")
+        self.assertEqual(metadata.get_private_key(self.cur), "priv2")
+
+if __name__ == "__main__":
+    unittest.main()
+
diff --git a/tests/test_property.py b/tests/test_property.py
new file mode 100644
index 0000000..0af4a87
--- /dev/null
+++ b/tests/test_property.py
@@ -0,0 +1,90 @@
+import unittest
+import psycopg
+from psycopg.rows import dict_row
+from ca_core import entity
+from ca_core import property as prop  # property.py
+
+class TestProperty(unittest.TestCase):
+    """Unit tests for property functions."""
+
+    def setUp(self):
+        self.conn = psycopg.connect("dbname=ca")
+        self.conn.autocommit = False
+        self.cur = self.conn.cursor(row_factory=dict_row)
+
+        # Clean tables before running
+        self.cur.execute("TRUNCATE TABLE property CASCADE;")
+        self.cur.execute("TRUNCATE TABLE entity CASCADE;")
+
+        # Insert a creator
+        self.creator_id = entity.insert_creator(self.cur, "Alice", "pubkeyA")
+
+        # Insert a regular person
+        self.person_id = entity.enroll_person(
+            self.cur, "Bob", "pubkeyB", self.creator_id
+        )
+
+        # Insert a group
+        self.group_id = entity.create_group(
+            self.cur, "Admins", "gpub", self.creator_id
+        )
+
+    def tearDown(self):
+        self.conn.rollback()
+        self.cur.close()
+        self.conn.close()
+
+    # -------------------------
+    # Set property
+    # -------------------------
+    def test_set_property(self):
+        prop.set_property(self.cur, self.person_id, "admin")
+        props = prop.get_properties(self.cur, self.person_id)
+        self.assertIn("admin", props)
+
+        # Setting same property again should not duplicate
+        prop.set_property(self.cur, self.person_id, "admin")
+        props = prop.get_properties(self.cur, self.person_id)
+        self.assertEqual(props.count("admin"), 1)
+
+    # -------------------------
+    # Delete property
+    # -------------------------
+    def test_delete_property(self):
+        prop.set_property(self.cur, self.person_id, "vip")
+        prop.delete_property(self.cur, self.person_id, "vip")
+        props = prop.get_properties(self.cur, self.person_id)
+        self.assertNotIn("vip", props)
+
+    def test_delete_nonexistent_property(self):
+        with self.assertRaises(ValueError):
+            prop.delete_property(self.cur, self.person_id, "nonexistent")
+
+    # -------------------------
+    # Get properties
+    # -------------------------
+    def test_get_properties_multiple(self):
+        prop.set_property(self.cur, self.person_id, "prop1")
+        prop.set_property(self.cur, self.person_id, "prop2")
+        prop.set_property(self.cur, self.person_id, "prop3")
+
+        props = prop.get_properties(self.cur, self.person_id)
+        self.assertCountEqual(props, ["prop1", "prop2", "prop3"])
+
+    def test_properties_independent_per_entity(self):
+        prop.set_property(self.cur, self.person_id, "p1")
+        prop.set_property(self.cur, self.group_id, "p2")
+
+        person_props = prop.get_properties(self.cur, self.person_id)
+        group_props = prop.get_properties(self.cur, self.group_id)
+
+        self.assertIn("p1", person_props)
+        self.assertNotIn("p2", person_props)
+
+        self.assertIn("p2", group_props)
+        self.assertNotIn("p1", group_props)
+
+
+if __name__ == "__main__":
+    unittest.main()
+