diff --git a/lib/cartodb/models/dataview/histograms/date-histogram.js b/lib/cartodb/models/dataview/histograms/date-histogram.js
index 8124f2db..34a42f9a 100644
--- a/lib/cartodb/models/dataview/histograms/date-histogram.js
+++ b/lib/cartodb/models/dataview/histograms/date-histogram.js
@@ -45,45 +45,45 @@ const nullsQueryTpl = ctx => `
     __cdb_nulls AS (
         SELECT
             count(*) AS __cdb_nulls_count
-        FROM (${ctx._query}) __cdb_histogram_nulls
-        WHERE ${ctx._column} IS NULL
+        FROM (${ctx.query}) __cdb_histogram_nulls
+        WHERE ${ctx.column} IS NULL
     )
 `;
 
 const dateBasicsQueryTpl = ctx => `
     __cdb_basics AS (
         SELECT
-            max(date_part('epoch', ${ctx._column})) AS __cdb_max_val,
-            min(date_part('epoch', ${ctx._column})) AS __cdb_min_val,
-            avg(date_part('epoch', ${ctx._column})) AS __cdb_avg_val,
+            max(date_part('epoch', ${ctx.column})) AS __cdb_max_val,
+            min(date_part('epoch', ${ctx.column})) AS __cdb_min_val,
+            avg(date_part('epoch', ${ctx.column})) AS __cdb_avg_val,
             min(
                 date_trunc(
-                    '${ctx._aggregation}', ${ctx._column}::timestamp AT TIME ZONE '${ctx._offset}'
+                    '${ctx.aggregation}', ${ctx.column}::timestamp AT TIME ZONE '${ctx.offset}'
                 )
             ) AS __cdb_start_date,
-            max(${ctx._column}::timestamp AT TIME ZONE '${ctx._offset}') AS __cdb_end_date,
+            max(${ctx.column}::timestamp AT TIME ZONE '${ctx.offset}') AS __cdb_end_date,
             count(1) AS __cdb_total_rows
-        FROM (${ctx._query}) __cdb_basics_query
+        FROM (${ctx.query}) __cdb_basics_query
     )
 `;
 
 const dateOverrideBasicsQueryTpl = ctx => `
     __cdb_basics AS (
         SELECT
-            max(${ctx._end})::float AS __cdb_max_val,
-            min(${ctx._start})::float AS __cdb_min_val,
-            avg(date_part('epoch', ${ctx._column})) AS __cdb_avg_val,
+            max(${ctx.end})::float AS __cdb_max_val,
+            min(${ctx.start})::float AS __cdb_min_val,
+            avg(date_part('epoch', ${ctx.column})) AS __cdb_avg_val,
             min(
                 date_trunc(
-                    '${ctx._aggregation}',
-                    TO_TIMESTAMP(${ctx._start})::timestamp AT TIME ZONE '${ctx._offset}'
+                    '${ctx.aggregation}',
+                    TO_TIMESTAMP(${ctx.start})::timestamp AT TIME ZONE '${ctx.offset}'
                 )
             ) AS __cdb_start_date,
             max(
-                TO_TIMESTAMP(${ctx._end})::timestamp AT TIME ZONE '${ctx._offset}'
+                TO_TIMESTAMP(${ctx.end})::timestamp AT TIME ZONE '${ctx.offset}'
             ) AS __cdb_end_date,
             count(1) AS __cdb_total_rows
-        FROM (${ctx._query}) __cdb_basics_query
+        FROM (${ctx.query}) __cdb_basics_query
     )
 `;
 
@@ -98,7 +98,7 @@ const dateBinsQueryTpl = ctx => `
                     SELECT GENERATE_SERIES(
                         __cdb_start_date::timestamptz,
                         __cdb_end_date::timestamptz,
-                        ${ctx._aggregation === 'quarter' ? `'3 month'::interval` : `'1 ${ctx._aggregation}'::interval`}
+                        ${ctx.aggregation === 'quarter' ? `'3 month'::interval` : `'1 ${ctx.aggregation}'::interval`}
                     )
                 ) AS __cdb_bins_array
             FROM __cdb_basics
@@ -117,7 +117,7 @@ const dateHistogramQueryTpl = ctx => `
             1,
             LEAST(
                 WIDTH_BUCKET(
-                    ${ctx._column}::timestamp AT TIME ZONE '${ctx._offset}',
+                    ${ctx.column}::timestamp AT TIME ZONE '${ctx.offset}',
                     __cdb_bins_array
                 ),
                 __cdb_bins_number
@@ -128,17 +128,17 @@ const dateHistogramQueryTpl = ctx => `
             date_part(
                 'epoch',
                 date_trunc(
-                    '${ctx._aggregation}', ${ctx._column}::timestamp AT TIME ZONE '${ctx._offset}'
-                ) AT TIME ZONE '${ctx._offset}'
+                    '${ctx.aggregation}', ${ctx.column}::timestamp AT TIME ZONE '${ctx.offset}'
+                ) AT TIME ZONE '${ctx.offset}'
             )
         )::numeric AS timestamp,
         date_part('epoch', __cdb_start_date)::numeric AS timestamp_start,
-        min(date_part('epoch', ${ctx._column}))::numeric AS min,
-        max(date_part('epoch', ${ctx._column}))::numeric AS max,
-        avg(date_part('epoch', ${ctx._column}))::numeric AS avg,
+        min(date_part('epoch', ${ctx.column}))::numeric AS min,
+        max(date_part('epoch', ${ctx.column}))::numeric AS max,
+        avg(date_part('epoch', ${ctx.column}))::numeric AS avg,
         count(*) AS freq
-    FROM (${ctx._query}) __cdb_histogram, __cdb_basics, __cdb_bins, __cdb_nulls
-    WHERE date_part('epoch', ${ctx._column}) IS NOT NULL
+    FROM (${ctx.query}) __cdb_histogram, __cdb_basics, __cdb_bins, __cdb_nulls
+    WHERE date_part('epoch', ${ctx.column}) IS NOT NULL
     GROUP BY bin, bins_number, bin_width, nulls_count, timestamp_start
     ORDER BY bin
 `;
@@ -177,7 +177,7 @@ module.exports = class DateHistogram extends BaseHistogram {
     _buildQueryTpl (ctx) {
         return `
             WITH
-            ${this._hasOverridenRange(ctx._override) ? dateOverrideBasicsQueryTpl(ctx) : dateBasicsQueryTpl(ctx)},
+            ${this._hasOverridenRange(ctx.override) ? dateOverrideBasicsQueryTpl(ctx) : dateBasicsQueryTpl(ctx)},
             ${dateBinsQueryTpl(ctx)},
             ${nullsQueryTpl(ctx)}
             ${dateHistogramQueryTpl(ctx)}
@@ -205,13 +205,13 @@ module.exports = class DateHistogram extends BaseHistogram {
         }
 
         const histogramSql = this._buildQueryTpl({
-            _override: override,
-            _query: this.query,
-            _column: this.column,
-            _aggregation: this._getAggregation(override),
-            _start: this._getBinStart(override),
-            _end: this._getBinEnd(override),
-            _offset: this._parseOffset(override)
+            override: override,
+            query: this.query,
+            column: this.column,
+            aggregation: this._getAggregation(override),
+            start: this._getBinStart(override),
+            end: this._getBinEnd(override),
+            offset: this._parseOffset(override)
         });
 
         debug(histogramSql);
diff --git a/lib/cartodb/models/dataview/histograms/numeric-histogram.js b/lib/cartodb/models/dataview/histograms/numeric-histogram.js
index 1df88adb..ea191bea 100644
--- a/lib/cartodb/models/dataview/histograms/numeric-histogram.js
+++ b/lib/cartodb/models/dataview/histograms/numeric-histogram.js
@@ -4,27 +4,27 @@ const debug = require('debug')('windshaft:dataview:numeric-histogram');
 const columnCastTpl = ctx => `date_part('epoch', ${ctx.column})`;
 
 const filterOutSpecialNumericValues = ctx => `
-        ${ctx._column} != 'infinity'::float
+        ${ctx.column} != 'infinity'::float
     AND
-        ${ctx._column} != '-infinity'::float
+        ${ctx.column} != '-infinity'::float
     AND
-        ${ctx._column} != 'NaN'::float
+        ${ctx.column} != 'NaN'::float
 `;
 
 const filteredQueryTpl = ctx => `
     __cdb_filtered_source AS (
         SELECT *
-        FROM (${ctx._query}) __cdb_filtered_source_query
-        WHERE ${ctx._column} IS NOT NULL
-        ${ctx._isFloatColumn ? `AND ${filterOutSpecialNumericValues(ctx)}` : ''}
+        FROM (${ctx.query}) __cdb_filtered_source_query
+        WHERE ${ctx.column} IS NOT NULL
+        ${ctx.isFloatColumn ? `AND ${filterOutSpecialNumericValues(ctx)}` : ''}
     )
 `;
 
 const basicsQueryTpl = ctx => `
     __cdb_basics AS (
         SELECT
-            max(${ctx._column}) AS __cdb_max_val, min(${ctx._column}) AS __cdb_min_val,
-            avg(${ctx._column}) AS __cdb_avg_val, count(1) AS __cdb_total_rows
+            max(${ctx.column}) AS __cdb_max_val, min(${ctx.column}) AS __cdb_min_val,
+            avg(${ctx.column}) AS __cdb_avg_val, count(1) AS __cdb_total_rows
         FROM __cdb_filtered_source
     )
 `;
@@ -32,8 +32,8 @@ const basicsQueryTpl = ctx => `
 const overrideBasicsQueryTpl = ctx => `
     __cdb_basics AS (
         SELECT
-            max(${ctx._end}) AS __cdb_max_val, min(${ctx._start}) AS __cdb_min_val,
-            avg(${ctx._column}) AS __cdb_avg_val, count(1) AS __cdb_total_rows
+            max(${ctx.end}) AS __cdb_max_val, min(${ctx.start}) AS __cdb_min_val,
+            avg(${ctx.column}) AS __cdb_avg_val, count(1) AS __cdb_total_rows
         FROM __cdb_filtered_source
     )
 `;
@@ -43,7 +43,7 @@ const iqrQueryTpl = ctx => `
         SELECT max(quartile_max) - min(quartile_max) AS __cdb_iqr
         FROM (
             SELECT quartile, max(_cdb_iqr_column) AS quartile_max from (
-                SELECT ${ctx._column} AS _cdb_iqr_column, ntile(4) over (order by ${ctx._column}
+                SELECT ${ctx.column} AS _cdb_iqr_column, ntile(4) over (order by ${ctx.column}
             ) AS quartile
             FROM __cdb_filtered_source) _cdb_quartiles
             WHERE quartile = 1 or quartile = 3
@@ -58,10 +58,10 @@ const binsQueryTpl = ctx => `
             CASE WHEN __cdb_total_rows = 0 OR __cdb_iqr = 0
             THEN 1
             ELSE GREATEST(
-                LEAST(${ctx._minBins}, CAST(__cdb_total_rows AS INT)),
+                LEAST(${ctx.minBins}, CAST(__cdb_total_rows AS INT)),
                 LEAST(
                     CAST(((__cdb_max_val - __cdb_min_val) / (2 * __cdb_iqr * power(__cdb_total_rows, 1/3))) AS INT),
-                    ${ctx._maxBins}
+                    ${ctx.maxBins}
                 )
             )
             END AS __cdb_bins_number
@@ -72,7 +72,7 @@ const binsQueryTpl = ctx => `
 
 const overrideBinsQueryTpl = ctx => `
     __cdb_bins AS (
-        SELECT ${ctx._override.bins} AS __cdb_bins_number
+        SELECT ${ctx.override.bins} AS __cdb_bins_number
     )
 `;
 
@@ -80,8 +80,8 @@ const nullsQueryTpl = ctx => `
     __cdb_nulls AS (
         SELECT
             count(*) AS __cdb_nulls_count
-        FROM (${ctx._query}) __cdb_histogram_nulls
-        WHERE ${ctx._column} IS NULL
+        FROM (${ctx.query}) __cdb_histogram_nulls
+        WHERE ${ctx.column} IS NULL
     )
 `;
 
@@ -89,11 +89,11 @@ const infinitiesQueryTpl = ctx => `
     __cdb_infinities AS (
         SELECT
             count(*) AS __cdb_infinities_count
-        FROM (${ctx._query}) __cdb_infinities_query
+        FROM (${ctx.query}) __cdb_infinities_query
         WHERE
-            ${ctx._column} = 'infinity'::float
+            ${ctx.column} = 'infinity'::float
         OR
-            ${ctx._column} = '-infinity'::float
+            ${ctx.column} = '-infinity'::float
     )
 `;
 
@@ -101,8 +101,8 @@ const nansQueryTpl = ctx => `
     __cdb_nans AS (
         SELECT
             count(*) AS __cdb_nans_count
-        FROM (${ctx._query}) __cdb_nans_query
-        WHERE ${ctx._column} = 'NaN'::float
+        FROM (${ctx.query}) __cdb_nans_query
+        WHERE ${ctx.column} = 'NaN'::float
     )
 `;
 
@@ -124,26 +124,26 @@ const histogramQueryTpl = ctx => `
         (__cdb_max_val - __cdb_min_val) / cast(__cdb_bins_number as float) AS bin_width,
         __cdb_bins_number AS bins_number,
         __cdb_nulls_count AS nulls_count,
-        ${ctx._isFloatColumn ? `${specialNumericValuesColumnDefinitionTpl()},` : ''}
+        ${ctx.isFloatColumn ? `${specialNumericValuesColumnDefinitionTpl()},` : ''}
         __cdb_avg_val AS avg_val,
         CASE WHEN __cdb_min_val = __cdb_max_val
             THEN 0
             ELSE GREATEST(
                 1,
                 LEAST(
-                    WIDTH_BUCKET(${ctx._column}, __cdb_min_val, __cdb_max_val, __cdb_bins_number),
+                    WIDTH_BUCKET(${ctx.column}, __cdb_min_val, __cdb_max_val, __cdb_bins_number),
                     __cdb_bins_number
                 )
             ) - 1
         END AS bin,
-        min(${ctx._column})::numeric AS min,
-        max(${ctx._column})::numeric AS max,
-        avg(${ctx._column})::numeric AS avg,
+        min(${ctx.column})::numeric AS min,
+        max(${ctx.column})::numeric AS max,
+        avg(${ctx.column})::numeric AS avg,
         count(*) AS freq
     FROM __cdb_filtered_source, __cdb_basics, __cdb_nulls, __cdb_bins
-        ${ctx._isFloatColumn ? `, ${specialNumericValuesCTETpl()}` : ''}
+        ${ctx.isFloatColumn ? `, ${specialNumericValuesCTETpl()}` : ''}
     GROUP BY bin, bins_number, bin_width, nulls_count, avg_val
-        ${ctx._isFloatColumn ? `, ${specialNumericValuesColumnTpl()}` : ''}
+        ${ctx.isFloatColumn ? `, ${specialNumericValuesColumnTpl()}` : ''}
     ORDER BY bin
 `;
 
@@ -167,14 +167,14 @@ module.exports = class NumericHistogram extends BaseHistogram {
 
     _buildQuery (psql, override, callback) {
         const histogramSql = this._buildQueryTpl({
-            _override: override,
-            _column: this._columnType === 'date' ? columnCastTpl({ column: this.column }) : this.column,
-            _isFloatColumn: this._columnType === 'float',
-            _query: this.query,
-            _start: this._getBinStart(override),
-            _end: this._getBinEnd(override),
-            _minBins: BIN_MIN_NUMBER,
-            _maxBins: BIN_MAX_NUMBER,
+            override: override,
+            column: this._columnType === 'date' ? columnCastTpl({ column: this.column }) : this.column,
+            isFloatColumn: this._columnType === 'float',
+            query: this.query,
+            start: this._getBinStart(override),
+            end: this._getBinEnd(override),
+            minBins: BIN_MIN_NUMBER,
+            maxBins: BIN_MAX_NUMBER,
         });
 
         debug(histogramSql);
@@ -186,13 +186,13 @@ module.exports = class NumericHistogram extends BaseHistogram {
         return `
             WITH
             ${filteredQueryTpl(ctx)},
-            ${this._hasOverridenRange(ctx._override) ? overrideBasicsQueryTpl(ctx) : basicsQueryTpl(ctx)},
-            ${this._hasOverridenBins(ctx._override) ?
+            ${this._hasOverridenRange(ctx.override) ? overrideBasicsQueryTpl(ctx) : basicsQueryTpl(ctx)},
+            ${this._hasOverridenBins(ctx.override) ?
                 overrideBinsQueryTpl(ctx) :
                 `${iqrQueryTpl(ctx)}, ${binsQueryTpl(ctx)}`
             },
             ${nullsQueryTpl(ctx)}
-            ${ctx._isFloatColumn ? `,${infinitiesQueryTpl(ctx)}, ${nansQueryTpl(ctx)}` : ''}
+            ${ctx.isFloatColumn ? `,${infinitiesQueryTpl(ctx)}, ${nansQueryTpl(ctx)}` : ''}
             ${histogramQueryTpl(ctx)}
         `;
     }