diff --git a/sql/histograms/histogram.cc b/sql/histograms/histogram.cc
index 289cb2b860b..c470feec5c5 100644
--- a/sql/histograms/histogram.cc
+++ b/sql/histograms/histogram.cc
@@ -2191,6 +2191,20 @@ double Histogram::get_equal_to_selectivity_dispatcher(const T &value) const {
   /* purecov: end deadcode */
 }
 
+// template helper functions for Histogram::get_selectivity_dispatcher()
+
+inline const CHARSET_INFO *charset_of(Item *item) {
+  return item->collation.collation;
+}
+
+inline enum_field_types data_type_of(Item *item) {
+  return item->data_type();
+}
+
+inline bool is_null(Item *item) {
+  return item->is_null();
+}
+
 static bool get_temporal(Item *item, Value_map_type preferred_type,
                          MYSQL_TIME *time_value) {
   if (item->is_temporal_with_date_and_time()) {
@@ -2236,7 +2250,8 @@ double Histogram::apply_operator(const enum_operator op, const T &value) const {
   }
 }
 
-bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
+template <class T>
+bool Histogram::get_selectivity_dispatcher(T *item, const enum_operator op,
                                            const TYPELIB *typelib,
                                            double *selectivity) const {
   switch (this->get_data_type()) {
@@ -2248,12 +2263,12 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
     }
     case Value_map_type::STRING: {
       // Is the character set the same? If not, we cannot use the histogram
-      if (item->collation.collation->number != get_character_set()->number)
+      if (charset_of(item)->number != get_character_set()->number)
         return true;
 
-      StringBuffer<MAX_FIELD_WIDTH> str_buf(item->collation.collation);
+      StringBuffer<MAX_FIELD_WIDTH> str_buf(charset_of(item));
       const String *str = item->val_str(&str_buf);
-      if (item->is_null()) return true;
+      if (is_null(item)) return true;
 
       *selectivity =
           apply_operator(op, str->substr(0, HISTOGRAM_MAX_COMPARE_LENGTH));
@@ -2261,7 +2276,7 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
     }
     case Value_map_type::INT: {
       const longlong value = item->val_int();
-      if (item->is_null()) return true;
+      if (is_null(item)) return true;
 
       *selectivity = apply_operator(op, value);
       return false;
@@ -2270,10 +2285,10 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
       assert(typelib != nullptr);
 
       longlong value;
-      if (item->data_type() == MYSQL_TYPE_VARCHAR) {
-        StringBuffer<MAX_FIELD_WIDTH> str_buf(item->collation.collation);
+      if (data_type_of(item) == MYSQL_TYPE_VARCHAR) {
+        StringBuffer<MAX_FIELD_WIDTH> str_buf(charset_of(item));
         const String *str = item->val_str(&str_buf);
-        if (item->is_null()) return true;
+        if (is_null(item)) return true;
 
         // Remove any trailing whitespace
         size_t length = str->charset()->cset->lengthsp(
@@ -2281,7 +2296,7 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
         value = find_type2(typelib, str->ptr(), length, str->charset());
       } else {
         value = item->val_int();
-        if (item->is_null()) return true;
+        if (is_null(item)) return true;
       }
 
       if (op == enum_operator::EQUALS_TO) {
@@ -2295,10 +2310,10 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
       assert(typelib != nullptr);
 
       longlong value;
-      if (item->data_type() == MYSQL_TYPE_VARCHAR) {
-        StringBuffer<MAX_FIELD_WIDTH> str_buf(item->collation.collation);
+      if (data_type_of(item) == MYSQL_TYPE_VARCHAR) {
+        StringBuffer<MAX_FIELD_WIDTH> str_buf(charset_of(item));
         const String *str = item->val_str(&str_buf);
-        if (item->is_null()) return true;
+        if (is_null(item)) return true;
 
         bool got_warning;
         const char *not_used;
@@ -2310,7 +2325,7 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
         value = static_cast<ulonglong>(tmp_value);
       } else {
         value = item->val_int();
-        if (item->is_null()) return true;
+        if (is_null(item)) return true;
       }
 
       if (op == enum_operator::EQUALS_TO) {
@@ -2322,14 +2337,14 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
     }
     case Value_map_type::UINT: {
       const ulonglong value = static_cast<ulonglong>(item->val_int());
-      if (item->is_null()) return true;
+      if (is_null(item)) return true;
 
       *selectivity = apply_operator(op, value);
       return false;
     }
     case Value_map_type::DOUBLE: {
       const double value = item->val_real();
-      if (item->is_null()) return true;
+      if (is_null(item)) return true;
 
       *selectivity = apply_operator(op, value);
       return false;
@@ -2337,7 +2352,7 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
     case Value_map_type::DECIMAL: {
       my_decimal buffer;
       const my_decimal *value = item->val_decimal(&buffer);
-      if (item->is_null()) return true;
+      if (is_null(item)) return true;
 
       *selectivity = apply_operator(op, *value);
       return false;
@@ -2361,6 +2376,10 @@ bool Histogram::get_selectivity_dispatcher(Item *item, const enum_operator op,
   /* purecov: end deadcode */
 }
 
+template
+bool Histogram::get_selectivity_dispatcher(Item *, const enum_operator,
+                                           const TYPELIB *, double *) const;
+
 bool Histogram::get_selectivity(Item **items, size_t item_count,
                                 enum_operator op, double *selectivity) const {
   if (get_raw_selectivity(items, item_count, op, selectivity)) return true;
diff --git a/sql/histograms/histogram.h b/sql/histograms/histogram.h
index 46dcc67b516..9b616088ee2 100644
--- a/sql/histograms/histogram.h
+++ b/sql/histograms/histogram.h
@@ -481,7 +481,8 @@ class Histogram {
 
     @return true on error (i.e the provided item was NULL), false on success.
   */
-  bool get_selectivity_dispatcher(Item *item, const enum_operator op,
+  template <class T>
+  bool get_selectivity_dispatcher(T *item, const enum_operator op,
                                   const TYPELIB *typelib,
                                   double *selectivity) const;