Added the error

1)ER_ARGUMENT_OUT_OF_RANGE: This error is thrown if the argument of the percentile function is not in the range [0,1]
  2)ER_ARGUMENT_NOT_CONSTANT: This error is thrown if the argument of the percnetile function is not constant in the
    entire partition of the window function

sql/item_windowfunc.h

@@ -730,7 +730,8 @@ class Item_sum_percentile_disc : public Item_sum_cume_dist,
 public:
   Item_sum_percentile_disc(THD *thd, Item* arg) : Item_sum_cume_dist(thd, arg),
                            Type_handler_hybrid_field_type(&type_handler_longlong),
-                           value(NULL), val_calculated(FALSE), first_call(TRUE),prev_value(0), order_item(NULL){}
+                           value(NULL), val_calculated(FALSE), first_call(TRUE),
+                           prev_value(0), order_item(NULL){}
 
   double val_real()
   {
@@ -780,21 +781,26 @@ public:
   {
     Item *arg = get_arg(0);
     if (arg->is_null())
-      return true;
+      return false;
 
     if (first_call)
     {
       prev_value= arg->val_real();
       if (prev_value >1 || prev_value < 0)
       {
+        my_error(ER_ARGUMENT_OUT_OF_RANGE, MYF(0));
+        has_error= TRUE;
         return true;
       }
       first_call= false;
     }
 
-    if(prev_value !=  arg->val_real())
+    double arg_val= arg->val_real();
+
+    if(prev_value !=  arg_val)
     {
-      // TODO(varun) need to add an error here , check the MDEV-12985 for the information
+      my_error(ER_ARGUMENT_NOT_CONSTANT, MYF(0));
+      has_error= TRUE;
       return true;
     }
 
@@ -821,6 +827,7 @@ public:
 
   void clear()
   {
+    has_error= false;
     val_calculated= false;
     first_call= true;
     value->clear();
@@ -890,36 +897,13 @@ public:
                   ((ceil(val) - val) * floor_value->val_real());
 
     return ret_val;
-
-  }
-  longlong val_int()
-  {
-    if (get_row_count() == 0 || get_arg(0)->is_null())
-    {
-      null_value= true;
-      return 0;
-    }
-    null_value= false;
-    return 0;
-  }
-
-  my_decimal* val_decimal(my_decimal* dec)
-  {
-    if (get_row_count() == 0 || get_arg(0)->is_null())
-    {
-      null_value= true;
-      return 0;
-      return 0;
-    }
-    null_value= false;
-    return ceil_value->val_decimal(dec);
   }
 
   bool add()
   {
     Item *arg = get_arg(0);
     if (arg->is_null())
-      return true;
+      return false;
 
     if (first_call)
     {
@@ -927,14 +911,17 @@ public:
       prev_value= arg->val_real();
       if (prev_value >1 || prev_value < 0)
       {
-        // TODO(varun) need to add an error here , check the MDEV-12985 for the information
+        my_error(ER_ARGUMENT_OUT_OF_RANGE, MYF(0));
+        has_error= TRUE;
         return true;
       }
     }
 
-    if (prev_value !=  arg->val_real())
+    double arg_val= arg->val_real();
+    if(prev_value !=  arg_val)
     {
-      // TODO(varun) need to add an error here , check the MDEV-12985 for the information
+      my_error(ER_ARGUMENT_NOT_CONSTANT, MYF(0));
+      has_error= TRUE;
       return true;
     }
 
@@ -966,12 +953,13 @@ public:
 
   enum Sumfunctype sum_func() const
   {
-    return PERCENTILE_DISC_FUNC;
+    return PERCENTILE_CONT_FUNC;
   }
 
   void clear()
   {
     first_call= true;
+    has_error= false;
     floor_value->clear();
     ceil_value->clear();
     floor_val_calculated= false;

sql/sql_window.cc

@@ -324,7 +324,7 @@ setup_windows(THD *thd, Ref_ptr_array ref_pointer_array, TABLE_LIST *tables,
   li.rewind();
   while((win_func_item= li++))
   {
-    if (win_func_item->check_order_list())
+    if (win_func_item->check_result_type_of_order_item())
       DBUG_RETURN(1);
   }
   DBUG_RETURN(0);
@@ -1078,12 +1078,13 @@ protected:
   {
     if (perform_no_action)
       return;
-
     List_iterator_fast<Item_sum> it(sum_functions);
     Item_sum *item_sum;
     while ((item_sum= it++))
     {
       item_sum->add();
+      if (item_sum->has_error)
+        return;
     }
   }
 
@@ -2809,6 +2810,12 @@ bool compute_window_func(THD *thd,
       {
         cursor_manager->notify_cursors_next_row();
       }
+
+      /* check if we found any error in the window function while calling the add function */
+
+      if (win_func->window_func()->has_error)
+        goto label;
+
       /* Return to current row after notifying cursors for each window
          function. */
       tbl->file->ha_rnd_pos(tbl->record[0], rowid_buf);
@@ -2821,6 +2828,7 @@ bool compute_window_func(THD *thd,
     rownum++;
   }
 
+label:
   my_free(rowid_buf);
   partition_trackers.delete_elements();
   end_read_record(&info);