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crates/connectors/ndc-postgres/src/schema.rs

@@ -437,6 +437,11 @@ fn make_procedure_type(
     let mut fields = BTreeMap::new();
     let object_type_name = format!("{name}_response");
 
+    // If int4 doesn't exist anywhere else in the schema, we need to add it here. However, a user
+    // can't filter or aggregate based on the affected rows of a procedure, so we don't need to add
+    // any aggregate functions or comparison operators. However, if int4 exists elsewhere in the
+    // schema and has already been added, it will also already contain these functions and
+    // operators.
     scalar_types
         .entry("int4".to_string())
         .or_insert(models::ScalarType {