diff --git a/lib/cartodb/models/aggregation/aggregation-query.js b/lib/cartodb/models/aggregation/aggregation-query.js
index f088e6b3..b987e24d 100644
--- a/lib/cartodb/models/aggregation/aggregation-query.js
+++ b/lib/cartodb/models/aggregation/aggregation-query.js
@@ -50,11 +50,20 @@ const SUPPORTED_AGGREGATE_FUNCTIONS = {
 };
 
 const aggregateColumns = ctx => {
-    let columns = Object.assign({
+    return Object.assign({
         _cdb_feature_count: {
             aggregate_function: 'count'
         }
     }, ctx.columns || {});
+};
+
+const aggregateColumnNames = ctx => {
+    let columns = aggregateColumns(ctx);
+    return Object.keys(columns).join(', ');
+};
+
+const aggregateColumnDefs = ctx => {
+    let columns = aggregateColumns(ctx);
     return Object.keys(columns).map(column_name => {
         const aggregate_function = columns[column_name].aggregate_function || 'count';
         const aggregate_definition = SUPPORTED_AGGREGATE_FUNCTIONS[aggregate_function];
@@ -89,7 +98,7 @@ const aggregationQueryTemplates = {
                     AVG(ST_Y(_cdb_query.the_geom_webmercator))
                 ), 3857
             ) AS the_geom_webmercator,
-            ${aggregateColumns(ctx)}
+            ${aggregateColumnDefs(ctx)}
         FROM (${ctx.sourceQuery}) _cdb_query, _cdb_params
         WHERE _cdb_query.the_geom_webmercator && _cdb_params.bbox
         GROUP BY
@@ -107,14 +116,14 @@ const aggregationQueryTemplates = {
         SELECT
         Floor(ST_X(_cdb_query.the_geom_webmercator)/_cdb_params.res)::int AS _cdb_gx,
         Floor(ST_Y(_cdb_query.the_geom_webmercator)/_cdb_params.res)::int AS _cdb_gy,
-        ${aggregateColumns(ctx)}
+        ${aggregateColumnDefs(ctx)}
         FROM (${ctx.sourceQuery}) _cdb_query, _cdb_params
         WHERE the_geom_webmercator && _cdb_params.bbox
         GROUP BY _cdb_gx, _cdb_gy
     )
     SELECT
         ST_SetSRID(ST_MakePoint(_cdb_gx*(res+0.5), _cdb_gy*(res+0.5)), 3857) AS the_geom_webmercator,
-        _cdb_feature_count
+        ${aggregateColumnNames(ctx)}
         FROM _cdb_clusters, _cdb_params
     `,
 
@@ -127,7 +136,7 @@ const aggregationQueryTemplates = {
         ), _cdb_clusters AS (
             SELECT
                 MIN(cartodb_id) AS cartodb_id,
-                ${aggregateColumns(ctx)}
+                ${aggregateColumnDefs(ctx)}
             FROM (${ctx.sourceQuery}) _cdb_query, _cdb_params
             WHERE _cdb_query.the_geom_webmercator && _cdb_params.bbox
             GROUP BY
@@ -136,7 +145,7 @@ const aggregationQueryTemplates = {
         ) SELECT
             _cdb_clusters.cartodb_id,
             the_geom, the_geom_webmercator,
-            _cdb_feature_count
+            ${aggregateColumnNames(ctx)}
         FROM
             _cdb_clusters INNER JOIN (${ctx.sourceQuery}) _cdb_query
             ON (_cdb_clusters.cartodb_id = _cdb_query.cartodb_id)