Fixup

sql/item_jsonfunc.h

@@ -712,7 +712,7 @@ class Item_func_json_arrayagg : public Item_func_group_concat
 protected:
   String *get_str_from_item(Item *i, String *tmp) override;
   String *get_str_from_field(Item *i, Field *f, String *tmp,
-                             const uchar *key, size_t offset,
+                             const uchar *key,
                              bool is_null) override;
   void cut_max_length(String *result,
                       uint old_length, uint max_length) const override;

sql/item_sum.h

@@ -601,6 +601,16 @@ class Item_sum :public Item_func_or_sum
   bool is_window_func_sum_expr() { return window_func_sum_expr_flag; }
   virtual void setup_caches(THD *thd) {};
   virtual void set_partition_row_count(ulonglong count) { DBUG_ASSERT(0); }
+  /*
+    While most Item_sum descendants employ standard aggregators configured
+    through Item_sum::set_aggregator() call, there are exceptions like
+    Item_func_group_concat, which implements its own custom aggregators for
+    deduplication values.
+    This function distinguishes between the use of standard and custom
+    aggregators by the object
+  */
+  virtual bool uses_non_standard_aggregator_for_distinct() const
+  { return false; }
   virtual Keys_descriptor *get_keys_descriptor(uint orig_key_size) const;
 protected:
   virtual bool is_packing_allowed(uint *total_length) const;
@@ -2013,6 +2023,8 @@ class Item_func_group_concat : public Item_sum
 
   virtual void cut_max_length(String *result,
                               uint old_length, uint max_length) const;
+  bool uses_non_standard_aggregator_for_distinct() const override
+  { return distinct; }
   bool setup(THD *thd, bool exclude_nulls);
 public:
   // Methods used by ColumnStore

sql/sql_statistics.cc

@@ -2549,7 +2549,7 @@ void Column_statistics_collected::init(THD *thd, Field *table_field)
       table_field->type() == MYSQL_TYPE_BIT ?
       new (thd->mem_root) Count_distinct_field_bit(table_field) :
       new (thd->mem_root) Count_distinct_field(table_field);
-    if (count_distinct && !count_distinct->setup(thd, max_heap_table_size))
+    if (count_distinct && count_distinct->setup(thd, max_heap_table_size))
     {
       /* Allocation failed */
       delete count_distinct;

sql/uniques.cc

@@ -309,23 +309,11 @@ static double get_merge_many_buffs_cost(THD *thd,
       these will be random seeks.
 */
 
-<<<<<<< HEAD
-double Unique_impl::get_use_cost(THD *thd,
-                                 uint *buffer, size_t nkeys, uint key_size,
-                                 size_t max_in_memory_size,
-                                 double compare_factor,
-                                 bool intersect_fl, bool *in_memory)
-||||||| parent of 2ff87b8cf9a (Add Unique support for packed keys)
-double Unique_impl::get_use_cost(uint *buffer, size_t nkeys, uint key_size,
+double Unique::get_use_cost(THD *thd,
+                            uint *buffer, size_t nkeys, uint key_size,
                             size_t max_in_memory_size,
                             double compare_factor,
                             bool intersect_fl, bool *in_memory)
-=======
-double Unique::get_use_cost(uint *buffer, size_t nkeys, uint key_size,
-                            size_t max_in_memory_size,
-                            double compare_factor,
-                            bool intersect_fl, bool *in_memory)
->>>>>>> 2ff87b8cf9a (Add Unique support for packed keys)
 {
   size_t max_elements_in_tree;
   size_t last_tree_elems;