diff --git a/unittests/test_error_handling.py b/unittests/test_error_handling.py
index 9962a0df48fa8ba1411d153a77ab975d3401363f..30912e753399991f090b71f385a762bceb9af9b9 100644
--- a/unittests/test_error_handling.py
+++ b/unittests/test_error_handling.py
@@ -29,9 +29,10 @@ children.
 import caosdb as db
 from caosdb.common.models import raise_errors
 # TODO: Import the relevant error classes once they have been finalized.
-from caosdb.exceptions import (EntityDoesNotExistError,
+from caosdb.exceptions import (AuthorizationException,
+                               EntityDoesNotExistError, EntityError,
                                EntityHasNoDatatypeError,
-                               TransactionError)
+                               TransactionError, UniqueNamesError)
 
 from pytest import raises
 
@@ -68,29 +69,55 @@ def test_entity_does_not_exist_error():
     code = 101
     ent = _add_error_message_to_entity(db.Entity(name="TestEnt"),
                                        code)
-
-    db.Property(name="TestProp"),
-                                        code)
     with raises(TransactionError) as e:
         raise_errors(ent)
     # There should be exactly one child
     assert len(e.errors) == 1
-    err=e.errors[0]
+    err = e.errors[0]
     # check type and entity of only child
     assert isinstance(err, EntityDoesNotExistError)
     assert err.entity.name == ent.name
 
 # TODO: remaining single error tests
+
+
 def test_entity_error():
     """Code 0; most basic."""
+    code = 0
+    ent = _add_error_message_to_entity(db.Entity(name="TestEnt"),
+                                       code)
+    with raises(TransactionError) as e:
+        raise_errors(e)
+    assert len(e.errors) == 1
+    err = e.errors[0]
+    assert isinstance(err, EntityError)
+    assert err.entity.name == ent.name
 
 
 def test_unique_names_error():
     """Code 152; name is not unique"""
+    code = 152
+    ent = _add_error_message_to_entity(db.Entity(name="TestEnt"),
+                                       code)
+    with raises(TransactionError) as e:
+        raise_errors(ent)
+    assert len(e.errors) == 1
+    err = e.errors[0]
+    assert isinstance(err, UniqueNamesError)
+    assert err.entity.name == ent.name
 
 
 def test_authorization_exception():
     """Code 403; transaction not allowed"""
+    code = 403
+    ent = _add_error_message_to_entity(db.Entity(name="TestEnt"),
+                                       code)
+    with raises(TransactionError) as e:
+        raise_errors(ent)
+    assert len(e.errors) == 1
+    err = e.errors[0]
+    assert isinstance(err, AuthorizationException)
+    assert err.entity.name == ent.name
 
 
 # #################### Children with children ####################
@@ -98,9 +125,9 @@ def test_authorization_exception():
 
 def test_unqualified_parents_error():
     """Code 116; parent does not exist"""
-    code=116
-    entity_does_not_exist_code=101
-    parent=_add_error_message_to_entity(
+    code = 116
+    entity_does_not_exist_code = 101
+    parent = _add_error_message_to_entity(
         db.RecordType(name="TestParent"),
         entity_does_not_exist_code)
     rec = _add_error_message_to_entity(db.Record(name="TestRecord"),