physical columns

common/proto/table_definition.proto

@@ -387,6 +387,31 @@ message PutTableDefinitionRequest {
 
   // Required physical/catalog name. Use table_name to keep the current name.
   string new_table_name = 8;
+
+  // Complete desired definition of an empty table, in catalog ordinal order.
+  // Aliases remain attached to their column IDs. Retained physical columns
+  // are not rebuilt or renamed; new columns use the existing append operation.
+  // Cannot be combined with remove_column_ids or add_columns. add_indexes and
+  // generated_aliases apply to the new columns in this definition.
+  optional EmptyTableDefinition replacement = 9;
+}
+
+message EmptyTableDefinition {
+  // Omitted existing columns are removed, subject to dependency checks.
+  // Retained generated companions follow their parent automatically.
+  repeated EmptyTableColumn columns = 1;
+}
+
+message EmptyTableColumn {
+  oneof column {
+    // Retains identity, configuration and dependencies. Generated companions
+    // must be retained through their parent, not listed separately.
+    int64 existing_column_id = 1;
+
+    // Same input as table creation. To change an existing column's type,
+    // omit its ID and supply a new definition; removal guards still apply.
+    ColumnDefinition new_column = 2;
+  }
 }
 
 message PutTableDefinitionResponse {