diff --git a/splitgraph/cloud/models.py b/splitgraph/cloud/models.py
index 93932b7f..bdf8e345 100644
--- a/splitgraph/cloud/models.py
+++ b/splitgraph/cloud/models.py
@@ -244,7 +244,7 @@ class UpdateExternalCredentialResponse(BaseModel):
 
 class ExternalTableRequest(BaseModel):
     options: Dict[str, Any] = {}
-    schema_: Optional[Dict[str, str]] = Field(alias="schema")
+    schema_: Dict[str, str] = Field(alias="schema", default={})
 
 
 class AddExternalRepositoryRequest(BaseModel):
diff --git a/splitgraph/core/types.py b/splitgraph/core/types.py
index c2688589..8d24bb2c 100644
--- a/splitgraph/core/types.py
+++ b/splitgraph/core/types.py
@@ -95,7 +95,7 @@ def dict_to_table_schema_params(
         t: (
             [
                 TableColumn(i + 1, cname, ctype, False, None)
-                for (i, (cname, ctype)) in enumerate((tsp.schema_ or {}).items())
+                for (i, (cname, ctype)) in enumerate(tsp.schema_.items())
             ],
             TableParams(tsp.options),
         )