diff --git a/schemas/api-config/projections.json b/schemas/api-config/projections.json
index c66dd1c..2f78b3d 100644
--- a/schemas/api-config/projections.json
+++ b/schemas/api-config/projections.json
@@ -12,13 +12,18 @@
             "description": "dataset query projection config",
             "properties": {
                 "select": {
-                    "type": "object",
-                    "description": "mongo db selector",
-                    "patternProperties": {
-                        "^[a-zA-Z0-9_]+(\\.[a-zA-Z0-9]+)*$": {
-                            "enum": [0, 1]
+                    "oneOf": [
+                        { "type": "null" },
+                        {
+                            "type": "object",
+                            "description": "mongo db selector",
+                            "patternProperties": {
+                                "^[a-zA-Z0-9_]+(\\.[a-zA-Z0-9]+)*$": {
+                                    "enum": [0, 1]
+                                }
+                            }
                         }
-                    }
+                    ]
                 }
             }
         }