diff --git a/lib/cartodb/models/aggregation/aggregation-query.js b/lib/cartodb/models/aggregation/aggregation-query.js
index f85a2bc6..53960c1a 100644
--- a/lib/cartodb/models/aggregation/aggregation-query.js
+++ b/lib/cartodb/models/aggregation/aggregation-query.js
@@ -132,10 +132,8 @@ const dimensionDefs = ctx => {
 // This is defined by the ctx.res parameter, which is the number of grid cells per tile linear dimension
 // (i.e. each tile is divided into ctx.res*ctx.res cells).
 const gridResolution = ctx => {
-    const factor = 256*0.00028/ctx.res;
     const minimum_resolution = 2*Math.PI*6378137/Math.pow(2,38);
-    let minimum_scale_denominator = minimum_resolution/factor;
-    return `(${factor}*GREATEST(!scale_denominator!,${minimum_scale_denominator}))::double precision`;
+    return `GREATEST(${256*0.00028/ctx.res}*!scale_denominator!, ${minimum_resolution})::double precision`;
 };
 
 // Notes: