diff --git a/api/s11_patterns.py b/api/s11_patterns.py
index 44bee01..236720c 100644
--- a/api/s11_patterns.py
+++ b/api/s11_patterns.py
@@ -11,6 +11,9 @@ def get_pattern_schema(name: str) -> dict[str, dict[str, Any]]:
 
 
 def get_pattern(name: str, id: str) -> dict[str, Any]:
+    p_one = try_read(name, f"select * from _pattern where id = '{id}'")
+    if p_one == None:
+        return {}
     pas = read_all(name, f"select * from patterns where id = '{id}' order by _order")
     ps = []
     for r in pas:
@@ -46,6 +49,10 @@ def set_pattern_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def set_pattern(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_pattern(name, cs.operations[0]['id']) == {}:
+        return ChangeSet()
     return execute_command(name, set_pattern_cmd(name, cs))
 
 
@@ -70,6 +77,10 @@ def add_pattern_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def add_pattern(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_pattern(name, cs.operations[0]['id']) != {}:
+        return ChangeSet()
     return execute_command(name, add_pattern_cmd(name, cs))
 
 
@@ -94,6 +105,10 @@ def delete_pattern_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def delete_pattern(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_pattern(name, cs.operations[0]['id']) == {}:
+        return ChangeSet()
     return execute_command(name, delete_pattern_cmd(name, cs))
 
 
diff --git a/api/s12_curves.py b/api/s12_curves.py
index 34780b0..a615564 100644
--- a/api/s12_curves.py
+++ b/api/s12_curves.py
@@ -16,7 +16,9 @@ def get_curve_schema(name: str) -> dict[str, dict[str, Any]]:
 
 
 def get_curve(name: str, id: str) -> dict[str, Any]:
-    c_one = read(name, f"select * from _curve where id = '{id}'")
+    c_one = try_read(name, f"select * from _curve where id = '{id}'")
+    if c_one == None:
+        return {}
     cus = read_all(name, f"select * from curves where id = '{id}' order by _order")
     cs = []
     for r in cus:
@@ -66,6 +68,10 @@ def set_curve_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def set_curve(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_curve(name, cs.operations[0]['id']) == {}:
+        return ChangeSet()
     return execute_command(name, set_curve_cmd(name, cs))
 
 
@@ -94,6 +100,10 @@ def add_curve_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def add_curve(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_curve(name, cs.operations[0]['id']) != {}:
+        return ChangeSet()
     return execute_command(name, add_curve_cmd(name, cs))
 
 
@@ -120,6 +130,10 @@ def delete_curve_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def delete_curve(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'id' not in cs.operations[0]:
+        return ChangeSet()
+    if get_curve(name, cs.operations[0]['id']) == {}:
+        return ChangeSet()
     return execute_command(name, delete_curve_cmd(name, cs))
 
 
diff --git a/test_tjnetwork.py b/test_tjnetwork.py
index ba39f98..74f6063 100644
--- a/test_tjnetwork.py
+++ b/test_tjnetwork.py
@@ -1850,6 +1850,8 @@ class TestApi:
 
         assert is_pattern(p, 'p0') == False
 
+        assert get_pattern(p, 'p0') == {}
+
         add_pattern(p, ChangeSet({'id' : 'p0', 'factors': [1.0, 2.0, 3.0]}))
 
         assert is_pattern(p, 'p0')
@@ -1874,6 +1876,8 @@ class TestApi:
         delete_pattern(p, ChangeSet({'id' : 'p0'}))
         assert is_pattern(p, 'p0') == False
 
+        assert get_pattern(p, 'p0') == {}
+
         self.leave(p)