From e8cd6856b52643c145a89e19adcce0dc23d8a96f Mon Sep 17 00:00:00 2001
From: Javier Goizueta <jgoizueta@gmail.com>
Date: Wed, 4 Apr 2018 17:18:56 +0200
Subject: [PATCH] Add missing aggregation columns to ST_AsMVT

Aggregation results always should have the cartodb_id and the feature count
---
 lib/cartodb/models/aggregation/aggregation-mapconfig.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/cartodb/models/aggregation/aggregation-mapconfig.js b/lib/cartodb/models/aggregation/aggregation-mapconfig.js
index d3666897..548f95d3 100644
--- a/lib/cartodb/models/aggregation/aggregation-mapconfig.js
+++ b/lib/cartodb/models/aggregation/aggregation-mapconfig.js
@@ -171,6 +171,8 @@ module.exports = class AggregationMapConfig extends MapConfig {
     _getLayerAggregationRequiredColumns (index) {
         const { columns, dimensions } = this.getAggregation(index);
 
+        let finalColumns = ['cartodb_id', '_cdb_feature_count'];
+
         let aggregatedColumns = [];
         if (columns) {
             aggregatedColumns = Object.keys(columns);
@@ -181,7 +183,7 @@ module.exports = class AggregationMapConfig extends MapConfig {
             dimensionsColumns = Object.keys(dimensions);
         }
 
-        return removeDuplicates(aggregatedColumns.concat(dimensionsColumns));
+        return removeDuplicates(finalColumns.concat(aggregatedColumns).concat(dimensionsColumns));
     }
 
     doesLayerReachThreshold(index, featureCount) {