diff --git a/api/s5_pipes.py b/api/s5_pipes.py
index e9a40a5..4c6c089 100644
--- a/api/s5_pipes.py
+++ b/api/s5_pipes.py
@@ -19,7 +19,9 @@ def get_pipe_schema(name: str) -> dict[str, dict[str, Any]]:
 
 
 def get_pipe(name: str, id: str) -> dict[str, Any]:
-    p = read(name, f"select * from pipes where id = '{id}'")
+    p = try_read(name, f"select * from pipes where id = '{id}'")
+    if p == None:
+        return {}
     d = {}
     d['id'] = str(p['id'])
     d['node1'] = str(p['node1'])
@@ -82,6 +84,10 @@ def set_pipe_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def set_pipe(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_pipe(name, cs.operations[0]['id']) == {}:
+        return ChangeSet()
     return execute_command(name, set_pipe_cmd(name, cs))
 
 
@@ -101,6 +107,10 @@ def add_pipe_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def add_pipe(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_pipe(name, cs.operations[0]['id']) != {}:
+        return ChangeSet()
     return execute_command(name, add_pipe_cmd(name, cs))
 
 
@@ -120,6 +130,10 @@ def delete_pipe_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def delete_pipe(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_pipe(name, cs.operations[0]['id']) == {}:
+        return ChangeSet()
     return execute_command(name, delete_pipe_cmd(name, cs))
 
 
diff --git a/test_tjnetwork.py b/test_tjnetwork.py
index af59d46..ad482a7 100644
--- a/test_tjnetwork.py
+++ b/test_tjnetwork.py
@@ -907,6 +907,8 @@ class TestApi:
         assert is_junction(p, 'j3')
         assert is_junction(p, 'j4')
 
+        assert get_pipe(p, 'p0') == {}
+
         add_pipe(p, ChangeSet({'id': 'p0', 'node1': 'j1', 'node2': 'j2', 'length': 100.0, 'diameter': 10.0, 'roughness': 0.1, 'minor_loss': 0.5, 'status': PIPE_STATUS_OPEN }))
         p0 = get_pipe(p, 'p0')
         assert p0['node1'] == 'j1'
@@ -959,6 +961,8 @@ class TestApi:
         links = get_links(p)
         assert len(links) == 0
 
+        assert get_pipe(p, 'p0') == {}
+
         self.leave(p)