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diff --git a/src/web/api/queries/sum/README.md b/src/web/api/queries/sum/README.md
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+<!--
+title: "Sum"
+sidebar_label: "Sum"
+custom_edit_url: https://github.com/netdata/netdata/edit/master/src/web/api/queries/sum/README.md
+learn_status: "Published"
+learn_topic_type: "References"
+learn_rel_path: "Developers/Web/Api/Queries"
+-->
+
+# Sum
+
+This module sums all the values in the time-frame requested.
+
+You can use `sum` to find the volume of something over a period.
+
+## how to use
+
+Use it in alarms like this:
+
+```
+ alarm: my_alarm
+    on: my_chart
+lookup: sum -1m unaligned of my_dimension
+  warn: $this > 1000
+```
+
+`sum` does not change the units. For example, if the chart units is `requests/sec`, the result
+will be again expressed in the same units. 
+
+It can also be used in APIs and badges as `&group=sum` in the URL.
+
+## Examples
+
+Examining last 1 minute `successful` web server responses:
+
+-   ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=min&after=-60&label=min)
+-   ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=average&after=-60&label=average)
+-   ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=max&after=-60&label=max)
+-   ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=sum&after=-60&label=1m+sum&value_color=orange&units=requests)
+
+## References
+
+-   <https://en.wikipedia.org/wiki/Summation>.
+
+
diff --git a/src/web/api/queries/sum/sum.c b/src/web/api/queries/sum/sum.c
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+++ b/src/web/api/queries/sum/sum.c
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+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "sum.h"
+
+// ----------------------------------------------------------------------------
+// sum
+
+
+
diff --git a/src/web/api/queries/sum/sum.h b/src/web/api/queries/sum/sum.h
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+++ b/src/web/api/queries/sum/sum.h
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+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef NETDATA_API_QUERY_SUM_H
+#define NETDATA_API_QUERY_SUM_H
+
+#include "../query.h"
+#include "../rrdr.h"
+
+struct tg_sum {
+    NETDATA_DOUBLE sum;
+    size_t count;
+};
+
+static inline void tg_sum_create(RRDR *r, const char *options __maybe_unused) {
+    r->time_grouping.data = onewayalloc_callocz(r->internal.owa, 1, sizeof(struct tg_sum));
+}
+
+// resets when switches dimensions
+// so, clear everything to restart
+static inline void tg_sum_reset(RRDR *r) {
+    struct tg_sum *g = (struct tg_sum *)r->time_grouping.data;
+    g->sum = 0;
+    g->count = 0;
+}
+
+static inline void tg_sum_free(RRDR *r) {
+    onewayalloc_freez(r->internal.owa, r->time_grouping.data);
+    r->time_grouping.data = NULL;
+}
+
+static inline void tg_sum_add(RRDR *r, NETDATA_DOUBLE value) {
+    struct tg_sum *g = (struct tg_sum *)r->time_grouping.data;
+    g->sum += value;
+    g->count++;
+}
+
+static inline NETDATA_DOUBLE tg_sum_flush(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) {
+    struct tg_sum *g = (struct tg_sum *)r->time_grouping.data;
+
+    NETDATA_DOUBLE value;
+
+    if(unlikely(!g->count)) {
+        value = 0.0;
+        *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY;
+    }
+    else {
+        value = g->sum;
+    }
+
+    g->sum = 0.0;
+    g->count = 0;
+
+    return value;
+}
+
+#endif //NETDATA_API_QUERY_SUM_H