From b01be6ae2dccd81fd81186d2ee9556c4037a283b Mon Sep 17 00:00:00 2001
From: mariadb-KristinaPavlova <kristina.pavlova@mariadb.com>
Date: Wed, 24 Sep 2025 10:58:17 +0300
Subject: [PATCH] fix: MCOL-5778 sum return null value due to nullif function

---
 dbcon/mysql/ha_mcs_execplan_helpers.cpp       |  2 ++
 .../columnstore/bugfixes/mcol-5778.result     | 16 ++++++++++++++
 .../columnstore/bugfixes/mcol-5778.test       | 21 +++++++++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 mysql-test/columnstore/bugfixes/mcol-5778.result
 create mode 100644 mysql-test/columnstore/bugfixes/mcol-5778.test

diff --git a/dbcon/mysql/ha_mcs_execplan_helpers.cpp b/dbcon/mysql/ha_mcs_execplan_helpers.cpp
index 66ffa35be..90331ab02 100644
--- a/dbcon/mysql/ha_mcs_execplan_helpers.cpp
+++ b/dbcon/mysql/ha_mcs_execplan_helpers.cpp
@@ -30,6 +30,8 @@ bool nonConstFunc(Item_func* ifp)
   {
     if (ifp->arguments()[i]->type() == Item::FUNC_ITEM && nonConstFunc(((Item_func*)ifp->arguments()[i])))
       return true;
+    if (ifp->arguments()[i]->type() == Item::CACHE_ITEM)
+      return true;
   }
 
   return false;
diff --git a/mysql-test/columnstore/bugfixes/mcol-5778.result b/mysql-test/columnstore/bugfixes/mcol-5778.result
new file mode 100644
index 000000000..8f346f5e4
--- /dev/null
+++ b/mysql-test/columnstore/bugfixes/mcol-5778.result
@@ -0,0 +1,16 @@
+DROP DATABASE IF EXISTS mcol5778;
+CREATE DATABASE mcol5778;
+USE mcol5778;
+create table test ( a double, b double ) engine=columnstore;
+insert into test values (100,100);
+select sum(a)/NULLIF(sum(b),0) from test;
+sum(a)/NULLIF(sum(b),0)
+1
+select sum(a)/NULLIF(b,0) from test;
+sum(a)/NULLIF(b,0)
+1
+select sum(a)/NULLIF(100,0) from test;
+sum(a)/NULLIF(100,0)
+1
+drop table test;
+DROP DATABASE mcol5778;
diff --git a/mysql-test/columnstore/bugfixes/mcol-5778.test b/mysql-test/columnstore/bugfixes/mcol-5778.test
new file mode 100644
index 000000000..0c5003df9
--- /dev/null
+++ b/mysql-test/columnstore/bugfixes/mcol-5778.test
@@ -0,0 +1,21 @@
+-- source ../include/have_columnstore.inc
+
+--disable_warnings
+DROP DATABASE IF EXISTS mcol5778;
+--enable_warnings
+
+CREATE DATABASE mcol5778;
+
+USE mcol5778;
+
+create table test ( a double, b double ) engine=columnstore;
+insert into test values (100,100);
+
+select sum(a)/NULLIF(sum(b),0) from test;
+
+select sum(a)/NULLIF(b,0) from test;
+
+select sum(a)/NULLIF(100,0) from test;
+
+drop table test;
+DROP DATABASE mcol5778;
\ No newline at end of file