Fixed bug mdev-11867.

If a window function with aggregation is over the result
set of a grouping query then the argument of the aggregate
function from the window function is allowed to be an
aggregate function itself.

1 files changed, 4 insertions, 0 deletions

diff --git a/sql/item_sum.h b/sql/item_sum.h
index 84049814ef9..940726b5d8e 100644
--- a/sql/item_sum.h
+++ b/sql/item_sum.h
@@ -340,6 +340,9 @@ private:
   */
   bool with_distinct;
 
+  /* TRUE if this is aggregate function of a window function */
+  bool window_func_sum_expr_flag;
+
 public:
 
   bool has_force_copy_fields() const { return force_copy_fields; }
@@ -551,6 +554,7 @@ public:
   virtual void cleanup();
   bool check_vcol_func_processor(void *arg);
   virtual void setup_window_func(THD *thd, Window_spec *window_spec) {}
+  void mark_as_window_func_sum_expr() { window_func_sum_expr_flag= true; }
 };